Student Question:

A + B ←s→ C is logically equivalent to A + C ←s→ B, and to B + C ←s→ A. Is the same true if the “+” (and) was an “or” instead? E.g., can we infer from A or B ←s→ C that A or C ←s→ B? Or does the same idea of logical equivalence/interchangeability not apply for “or” statements?

Tutor Response:

For (A + B) ←s→ C (i.e., a "some" statement with an "and"), swapping the variables around in the way you're proposing is logically equivalent, but this doesn't work with "or" statements.

For the "and" structure, let's have A = “left-handed,” B = “wears glasses,” and C = “is a lawyer.” Then “(A + B) ←s→ C” means there exists at least one person who is left-handed, wears glasses, and is a lawyer. Looking at it this way, it becomes intuitive why we can re-group the terms: saying “some left-handed glasses-wearers are lawyers” is the same fact as saying “some left-handed lawyers wear glasses” or “some glasses-wearing lawyers are left-handed,” because all we're doing is describing the same triple-overlap person from different angles.

By contrast, with "(A or B) ←s→ C" (i.e., a "some" statement with an "or"), rather than bundling traits together; the "or" only guarantees the example has at least one of the options, which means the overlap structure can be much more narrow. Using the same labels, “(A or B) ←s→ C” means: there exists at least one lawyer who is either left-handed or wears glasses (or both). This could be true just through the existence of a left-handed lawyer who does not wear glasses, even if no lawyers at all wear glasses.

In that scenario, we can't safely swap the terms the way we could with the "and" statement, because there may be no single person who connects B to the rest. In other words, with an "or" relationship, the entire relationship can be true through the presence of A, the presence of B, or the presence of both, so the interchangeability you felt with the "and" statement (where one example has A, B, and C together) doesn't carry over.

Student Question:

I'm going to be so honest here, I get why the other answers aren't right but on the AT and BR, I strictly did not choose D because I didn't know where the "or more" was coming from since the stimulus says that anarchist novels have two (and only two because we cant assume that there's more than two, can we??)

Tutor Response:

You're right that nothing in the stimulus provides a need for the "or more" phrase in D. In other words, if we were to remove this phrase so that D read "It is permissible to ban a novel that would cause society more harm than good if the novel has (exactly) two objectionable characteristics", D is still just as good of an answer, as it still fully justifies the author's argument.

It's helpful to keep in mind, though, that for Pseudo-Sufficient Assumption questions like this one, as well as for Sufficient Assumption questions, it's completely fine if the answer choice gives us more than what we need or is broader in scope than other alternatives we could imagine. Here, if we apply the rule D gives us to the specific situation in the argument (anarchist novels, which all have two objectionable characteristics), we've triggered the sufficient condition of D's rule ("if the novel has two or more objectionable characteristics"). The fact that the rule would also be triggered by a romance novel that has three objectionable characteristics, or a science fiction novel with five objectionable characteristics, is irrelevant. What matters is that the rule still justifies the censor's reasoning, and from that we can be confident D is the correct answer.

Student Question:

I’m so confused. How does the dioxin decomposing away from the fish have any bearing on whether or not dioxin causes the hormone concentration to change?

Tutor Response:

The relevant factor here isn't so much that the dioxin is decomposing away from the fish, but that the dioxin itself is away from the fish. This connects to a few of the facts established in the stimulus:

• Presence of this chemical (dioxin) in the water around the fish changes their hormone concentrations

• This chemical is being put into the water by mill activity. When the mills close (i.e., when they stop adding new dioxin to the water), fish’s hormone concentrations go back to normal pretty quickly

• What C is adding: Without new dioxin being added to the water (i.e., with the mills being closed), the dioxin in the water around the fish is typically moved away by the current within a few hours

The author is arguing that dioxin is not likely to be the cause of the fish's reproductive issues, but C provides a reason for thinking that the evidence the author presents actually supports dioxin being the cause: it shows how dioxin as the explanation can account for the fact that, when the mills shut down, the fish's hormone levels quickly return to normal. Because of C, the other fact that the author is attempting to use as support (the fact that dioxin decomposes very quickly) becomes irrelevant: the rate at which dioxin is decomposing doesn't matter, as the reason fish's hormone levels recover when the mills are shut down could be because the dioxin has been moved away from the fish.

Student Question:

I initially said C, because A and B mention "good" and D and E seem irrelevant. my confusion here is the good vs better. maybe, it is relevant that the stimulus left out "good." the author states oppose -> better. but , per B and A, what if it was not that case that oppose -> good nor the case that good -> oppose. I think maybe I was on the right path with C- that there are other issues. but at this point it's out of scope. A almost brings it in to scope, by saying that the tax issue doesn't contribute to goodness. even though they use different terms (good/better). maybe I should consider that to be "better" one must have more "good" attributes. and, if the tax issue does not do this, than the argument is weakened. my only issue here is that who is to say that supporting higher taxes isn't a sufficient condition for bad leadership? if its all marginal according to the author

Tutor Response:

In assessing the different answer choices, I would first try to identify any significant or questionable assumptions that jump out in reading the stimulus. Here, the author's argument is:

1. T opposes higher taxes, and the other candidates support higher taxes.

2. Many people agree that opposing higher taxes = being a better leader than someone who supports higher taxes.

---

T is a better leader than the other candidates.

This argument has a significant flaw: it's using the fact that "many people agree that X is true" as sufficient evidence for establishing that X is true. But what if the people who agree that X is true are wrong? Examples abound of popular / widespread misconceptions, and we know that many people believing something doesn't necessarily mean that it's true.

Answer Choice A directly captures and reinforces this flaw. While it's true that the answer choice refers to "good leadership" whereas the stimulus mentions only "better" and "best" leadership, A still provides reason for doubting the author's hidden assumption. Looking back at our sketch of the stimulus above, if opposing higher taxes is not relevant in assessing good leadership, then neither Premise 1 nor Premise 2 is actually providing a compelling reason to think that Thompson is a good leader or a better leader than anyone else.

One point it can be helpful to keep in mind is that, for A to be the correct answer, we don't need to establish it isn't true that "supporting higher taxes is a sufficient condition for bad leadership". A is just showing that the author hasn't given us any meaningful evidence to conclude that supporting higher taxes is sufficient to make someone a worse leader. In other words, the burden of proof is on the author. Rather than needing to affirmatively show that the author's conclusion is wrong, the right answer choice just needs to undermine the link between the evidence the author is offering us and the conclusion they're attempting to support.

Student Question:

Hi, when I saw AC A, I was concerned with the word “order.” Am I to understand anything that is coherent has order? Additionally, I’m not fully understanding why AC B is not a better answer than AC A — I understood “false understanding” as: the dream didn’t even happen, but the person who left he room is making up a dream, and therefore making a false understanding of what actually happened. Thank you!

Tutor Response:

To establish that A is the correct answer, we don't need to reach a Must Be True-level certainty that "Coherent → Order", but there is a close overlap between the standard interpretations of these words that we should take into account. Here, “order” is being used in a broad way (i.e., structure, pattern, organization, coherence). If something is truly coherent (it “hangs together" / has internal consistency), it will typically have some degree of “order” in that sense.

Additionally, we're told that the person "constructs a dream narrative". The act of construction seems to suggest that they're creating some sense of organization / structure (i.e., a sense of order). Answer Choice A says that, when someone presumes there's an underlying coherent structure (as the person asking the questions in the game is doing), they'll often impose one, taking arbitrary inputs and fitting them into a narrative that makes sense (i.e., is coherent).

Regarding why B isn’t better: B makes a comparative claim the stimulus doesn’t support. B says a person is “less apt” to reach a false understanding of what someone says than to make no sense out of it at all; in other words, we're more likely to fail to make any sense of what someone is saying than to misunderstand what someone is saying. In the game, however, there is no real message/dream being communicated at all. In this case, the person isn't misunderstanding what was said, but is instead treating random answers as if they reflect a meaningful, ordered dream, and then building coherence from that presumption.

B would fit better if the group actually did relay a dream (so there's actual content to misunderstand) and the point was that people tend to be totally confused rather than misunderstand the dream, but that's not what the example in the stimulus shows.

Student Question:

Hello, I got this question correct but wanted to make sure my reasoning was correct. I diagrammed Judges head → Tree so the contrapositive of this would be /Tree → /Judges head. So I thought “no tree” is equivalent to building → judges head.

Tutor Response:

You're right that the stimulus establishes "Judge's head → Tree", and so we know the contrapositive ("/Tree → /Judge's head") follows as well.

From here, I would be careful: you're right that, if a building is on one side, we know that a tree is not on that same side (as "each face of any coin portrays one of four things"). This doesn't mean that "/Tree" and "Building" are interchangeable, though: a coin that doesn't have a tree on one side could have either a building or an explorer's head (or both) on it.

The way to confirm D is the right answer here is actually a bit simpler, relying on the original conditional you noted: Judge's head → Tree. If we have a judge's head on one side, then we have a tree on the other. Since each side of a coin has only one of the four things, a tree being on that other side means that no other thing (including a building) is on that other side. In other words, "Judge's head → / Building", or "Building → / Judge's head", which is what D captures.

Student Question:

Answer choice E says “They believe”. How can we infer what they believe? In the first paragraph it is the Author saying that it may be useful for plaintiffs but how can you jump for their research is useful for plaintiffs to they believe themselves. Maybe they didn't have plaintiffs in mind or they disagree with the author?

Tutor Response:

The evidence for this inference (that Zirkel and Schoenfeld "believed that the information generated by outcomes analysis would be relevant for plaintiffs") isn't just the fact that their research can be useful to plaintiffs; you're right that this wouldn't be a reasonable jump. However, in the passage we're given a few more concrete pieces of information about what these two actually believe and favor:

1. They're among the scholars who have "justifiably criticized traditional legal research for its focus on a few cases that may not be representative and its fascination with arcane matters that do not affect real people with real legal problems." In plain English: Zirkel and Schoenfeld believe that the normal way of doing legal research is flawed because of its failure to focus enough on problems actually relevant to people.

2. They have "enthusiasm for the 'outcomes analysis' technique," which involves "counting the number of successful and unsuccessful plaintiffs."

3. Their studies have shown how using social science tools in case law analysis can "be used to serve the interests of... prospective plaintiffs."

It's this combination of evidence that provides support for the inference in E. Zirkel and Schoenfeld (a) criticize one approach for failing to be relevant to people, (b) propose an alternative approach that can be useful for real people (plaintiffs), and (c) are enthusiastic about that alternative approach. The fact that they're enthusiastic rather than critical of this alternative approach supports the idea that they think this alternative approach lacks the basis for their criticism of the traditional approach: the traditional approach's failure to be relevant to real people. That's the inference E is capturing.

Student Question:

I’m confused in question PT141.S2.Q12 on how you would tell it’s a sufficient assumption question instead of a necessary assumption question. I thought it was necessary assumption, and so I was looking for an answer that told me “at least one member gave consent” so the “most” in answer choice A threw me off. What are some common ways to tell whether it’s sufficient or necessary?

Tutor Response:

In terms of distinguishing which assumption type (sufficient vs. necessary) the question is asking for, each assumption type has a few distinctive keywords that the question almost always uses. If you can commit those to memory, it'll become much easier to identify which assumption type a question is looking for:

Sufficient: "follows logically", "properly inferred", "properly drawn"

You can just memorize these terms, but it can also be helpful to see that each is asking, in slightly different ways: if we take the answer choice to be true, which one makes the argument valid / guarantees that the conclusion must be true if the premises are also true.

• The conclusion of the argument follows logically if which one of the following is assumed?

• Which one of the following, if assumed, allows the conclusion to be properly inferred?

• The argument’s conclusion is properly drawn if which one of the following is assumed?

Necessary: "relies on", "requires", "depends on"

Each of these is getting at the idea that, without this assumption, the argument falls apart.

• The argument depends on assuming which one of the following?

• Which one of the following is an assumption required by the argument?

• Which one of the following is an assumption on which the argument relies?

Student Question:

I am unsure with (A) for two reasons.

1) From a MBT perspective, I was thrown off by the word "significantly". It seems that (A) without the word significantly would also seem to weaken the argument if negated, and thus (A) with the word "significantly" looked unnecessary.

2) I was excepting an AC with a comparison because the stimulus was also comparing between the level of danger in driving when conversing on a cell phone vs when conversing with a passenger. I thought (A) was committing an absolute vs. relative flaw.

I thought we only needed to support that conversing on the cell phone was more dangerous than conversing with a passenger while driving. I thought (A) went beyond this, and sought to show that conversing with a passenger is actually dangerous/increases the risk of an accident. Why can't it be that conversing with a passenger just makes driving extremely safe, and conversing on a phone has zero or slightly positive effect on driving?

Tutor Response:

1) The “significantly” concern

Though “significantly” feels like an extra word, it's actually helping A land at the right strength for a necessary assumption. The expert's reasoning needs the idea that someone talking with the driver during difficult moments is a meaningful source of added danger unless it's helpful warnings. If this isn't the case, then the whole “phone caller can’t see, passenger can” contrast wouldn't matter for safety. If we negate A—talking during difficult situations does not significantly increase risk even when the speaker isn't providing helpful warnings—then the link the safety expert is trying to establish breaks: the phone caller's inability to recognize difficulty no longer supports the idea that this situation is “more dangerous.”

We can understand "significantly" in this context as "meaningful" or "non-negligible." You're right that a slightly revised version of the answer choice that removes this word ("Speaking to a driver during a difficult driving situation increases the risk of an accident, unless the speaker is providing helpful warnings") is also an assumption the argument requires, but the version with "significantly" is still something the argument needs. For example, imagine that talking during a difficult driving moment technically increases accident risk, but only by a vanishingly small amount, such as one extra accident per ten million instances of talking while driving. In that case, it's hard to say cell phone conversation is “more dangerous” in any meaningful sense, because the difference the expert is pointing to (phone caller can't go quiet or warn at the right moment) wouldn't translate into a practical or measurable safety gap. The conclusion is a comparative claim about danger, and that kind of claim usually needs the underlying risk difference to be large enough to matter, not just a microscopic uptick that's statistically or practically negligible. So “significantly” is the test-writers' way of baking in the idea that the expert is assuming that talking at the wrong times isn't merely technically riskier, but riskier enough that the passenger's ability to adapt (quiet or warn) can plausibly make passenger conversation safer than phone conversation.

2) The comparison / “absolute vs. relative” concern

You're right that the stimulus is comparative (cell phone conversation is more dangerous than passenger conversation), so it makes sense to expect an assumption that's directly comparative (i.e., “cell phone conversations raise risk of accidents more than passenger conversations”). However, the expert's evidence isn't a direct comparison of risk levels—it's a mechanism: during difficult driving situations, a passenger can usually stop talking or warn, while a phone caller can't. To turn that mechanism into a safety conclusion, the missing assumption has to be a rule about what happens to risk when someone talks during difficult moments (other than helpful warnings), which is exactly what A supplies.

Additionally, A doesn't require us to conclude that “passenger conversation is highly dangerous overall.” It only says that talking during difficult situations is risky other than giving warnings; that actually supports the comparative claim that passengers are less dangerous because they're more likely to be quiet or warn at the right time. Regarding your last hypothetical, even if we take A to be true, passenger talk could still be extremely safe (or even beneficial) if it consists of helpful warnings. What the argument couldn't allow is that non-helpful talking in difficult moments has basically no safety downside, because then the phone-vs-passenger visibility difference wouldn't establish that the former is “more dangerous” than the latter.

Student Question:

isn’t C too strong for NA? i predicted the answer to be something like “at least some fish CAN die from not trying new food,” but this says that some did die.

Tutor Response:

You're right that something like "Some fish raised in traditional hatcheries can die because they are too timid in their foraging for food" would also be a necessary assumption here, but there can be assumptions of varying levels of strength each of which are necessary for the argument. In this case, the stronger version presented in C is also necessary: The author is making an argument about a difference in likelihood of survival. If we negate C (i.e., if no fish raised in traditional hatcheries die because they're too timid in foraging for food), then we don't have any reason for thinking the difference between the experimental- and traditional-hatchery fish's boldness in trying new foods supports a difference in their likelihoods of survival. In other words, the argument still falls apart, so we know that C must be a necessary assumption.

Student Question:

still don’t understand is this question more in reverse because of the conclusion in the argument says its not supported .

Tutor Response:

You're right that we can think of this question as "in reverse" in the sense that we're being asked to weaken an argument trying to establish that someone else's conclusion isn't supported. However, we can still approach it as a standard weakening question: try to undermine the premises and the conclusion of the argument, without directly contradicting the premises themselves.

Premises: Lab animals fed reduced-calorie diets lived longer than lab animals not on those diets. This is because reducing their diets brought their calorie intake down from eating much more than they would naturally back to their optimal levels.

--

Conclusion: There is no reason to think that giving North American people reduced-calorie diets could similarly lead to increased lifespans (in other words, doctors' claims that this would work owing to the lab animal results aren't supported)

The correct answer should show that, even when we grant the premises to the true, we still have reason to doubt the truth of the author's conclusion. Here, let's assume all the lab animal study results are true, but that A is also true. This would mean that North Americans actually are similar to the lab animals in a key way: current calorie intake is much higher than optimal levels. The author is trying to draw a distinction between the lab animals and North Americans, but if A is true, the author doesn't actually demonstrate any relevant difference between the two groups. Given this, we'd have no reason from the stimulus to suspect that reducing North Americans' caloric intake wouldn't produce a similar result to what happened to the lab animals on a reduced-calorie diet: extended lifespans.

Student Question:

shouldn’t an alternate hypothesis actually weaken the hypothesis given in the stimulus? i felt that B gives an additional possible mechanism to explain the observations, but it doesn’t directly attack or even address the given hypothesis. what if having a larger size is developed for BOTH surviving winters AND defending predators? the answer choice doesn’t seem to give any reason to doubt this. i thought that since C goes at the connective point of predators it was more relevant (like what if insects just suck on the skin so the size doesn’t matter for lake sickelbacks, whereas size does matter for the large fish predators that need to be able to chow down on ocean sicklebacks?).

Tutor Response:

If an answer choice provides a compelling alternative explanation, it can actually weaken the stimulus without directly attacking the author's proposed explanation. For example:

Phenomenon: My lawn is wet.

Conclusion / Proposed Explanation: It must have recently rained.

If we were asked to weaken this argument, a strong answer choice could be "my lawn has a sprinkler system that recently started up." This provides an alternative explanation for why the grass is wet, but it's not providing information that directly attacks the idea it could have recently rained (i.e., "The meteorologists predicted sun today", "It wasn't raining just a county over", "This area is in the middle of a drought"). Instead, it's giving us reason to doubt that the author's hypothesis is as strongly supported by the premises as we might have initially thought, and the reason for this additional doubt is just the existence of a plausible alternative explanation.

Similarly, in this problem, B offers an alternate hypothesis for explaining the lake stickleback's larger size: perhaps it's because this larger size helps them to survive cold winters. You're right this doesn't rule out or disprove the author's proposed explanation that the larger size is a better defense against the lake stickleback's predators than armor is, and it is possible that both could be true at the same time. However, just by introducing a plausible alternative explanation, we've weakened the argument by giving additional reason to doubt that, even if the premises are true, the author's conclusion / proposed explanation must also be true.

Regarding why C is wrong: it would only weaken the author's argument if we make the additional assumption that a larger size wouldn't be more effective than armor in enabling these fish to defend themselves against insect predators. Neither the stimulus nor the information in C establishes this link, so we're not able to conclude that C undermines the author's proposed hypothesis.

Student Question:

I feel like I'm going a little bit crazy here. I ruled out A because I believed it offered an alternative reason for why there might be an overall decrease in negative environmental effects of the acid rain, which would therefore weaken the argument that the decrease in acidic pollutants led to the decrease in negative effects.

Tutor Response:

The mechanism that you're naming (introducing an alternative explanation) is a common one for weakening arguments on the LSAT, but the reason it doesn't have that effect here is because of the structure of the argument: The author's conclusion is that "we can expect an overall decrease in the negative environmental effects of acid rain", and the support provided is the decrease in the amount of the pollutants that cause acid rain. With this structure, Answer Choice A has no impact on (or, perhaps, provides slight independent support for) the conclusion that we can expect a decrease in acid rain's negative effects.

This is a different structure than if the author were responding to a phenomenon and, as the main point of their argument, identifying a decrease in acidic pollutants as their proposed explanation for that phenomenon: i.e., "Over the last several decades, there has been an overall decrease in the negative effects of acid rain. This means that the amount of acidic pollutants released into the air must have decreased throughout the world over the last several decades."

In that case, you're right that answer choice A could weaken the argument by providing an alternative explanation as to what caused the overall decrease in negative environmental effects of acid rain. In the version of the stimulus we're presented with, however, the core claim the author is trying to prove is that we should expect an overall decrease, not that a particular explanation for what is contributing to the decrease is the best explanation. The direction of the relationships of support here is why A isn't weakening the columnist's argument as it's presented in the problem.

Student Question:

I am confused in flaw questions when the correct answer should be overlooks the possibility or takes for granted between stimuli that ask you to identify the flaw and stimuli that asks what makes the argument vulnerable to criticism.

Tutor Response:

In practice, there usually isn’t a meaningful difference between problems that ask for “a flaw” and ones that ask what makes the argument “vulnerable to criticism”: both are basically asking you to identify the underlying reasoning mistake the author is making.

Similarly, the difference between answer choice language like “takes for granted that…” and “overlooks/ignores the possibility that…” is mostly a wording shift around that same idea: “takes for granted” frames the problem as an unstated but not self-evident assumption the author is treating as true, while “overlooks the possibility” frames it as failing to consider an alternative scenario that would weaken the conclusion.

In this specific argument, the reformer notes that the crime rate hasn’t significantly decreased over 20 years, while imprisonment and prison spending have increased. From this, they conclude that putting more people in prison cannot help reduce crime. The flaw is the reformer assuming that if increased imprisonment were helping, the crime rate would need to have decreased over the last 20 years. However, it’s entirely possible that the crime rate would have risen significantly over those 20 years if imprisonment hadn’t increased, meaning imprisonment could still be helping by preventing an increase rather than producing a decrease. That’s why the correct answer is about ignoring a possibility: it points out the missing alternative that undermines the jump the author attempts to make from “no decrease in crime rate” to “no effect on reducing crime.”

Student Follow-Up Question:

I understand why AC B is correct for the sunscreen passage. However, I’m afraid I’m not yet fully grasping the difference between why AC D works for the stretching passage, but AC E doesn’t for the sunscreen passage.

Is it the way the passages are structured? E.g. the sunscreen passage is not necessarily comparing one group to another group (sunscreen users vs sunscreen non-users), whereas the stretching passage is (stretchers vs non-stretchers).

Tutor Response:

It's true that the conclusions have a similar form: the author in the sunscreen stimulus is attempting to argue that using sunscreen is unlikely to reduce a person's risk of developing skin cancer, and the author of the jogging stimulus is arguing that stretching before jogging doesn't help to prevent injuries.

However, the difference you're noting between the two stimuli is definitely relevant, as we'll want to look at the ways in which each author is attempting to support their conclusion:

1. The sunscreen author points to a correlation between higher incidences of sun-related skin cancer over the last 25 years and increasingly widespread use of sunscreen.

2. The medical researcher points to two groups of equal numbers of joggers (one group who stretched before jogging and another group who didn't) who incurred roughly the same number of injuries.

With Weakening questions, we're being asked to undermine the support between the premises and conclusion. This often involves providing further information that exposes a gap in the argument or makes the premises less relevant to the conclusion. Given this task, the way in which the author is supporting their argument significantly impacts how the argument can be most weakened.

In the jogging case, D provides a reason for thinking that, even if the support the author provides (that both jogging groups experienced the same amount of injuries) for their conclusion is true, we should be more skeptical of the conclusion the author is drawing. In the sunscreen problem, even if we take E to be true, it doesn't give us a reason to be more skeptical of whether the author's conclusion follows from their premises than we were from reading just the stimulus: we still don't know whether using sunscreen is reducing the users' risk of skin cancer, and E doesn't tip the scales either way.

For E to be having a similar effect as answer choice D in the jogging problem, we'd have to significantly rewrite the stimulus. We'd want to change the primary support from "correlation between increased skin cancer incidences and more widespread use of sunscreen" to something like "Two groups of 100 people each had the same amount of sun exposure; one group applied sunscreen reliably before such sun exposure whereas the other didn't, but each group had similar rates of sun-related skin cancer". We would then likely also want to adjust the "believe" in answer choice E to "know". At this point, however, we'd be dealing with a very different stimulus.

Student Follow-Up Question:

Thanks for your help! This makes more sense. So just to clarify, because of the last bit "that even the critics acknowlege" that is why we can assume there is tremendous support, because in the stimulus, the critics do not acknowledge such a lack of tremendous support?

Tutor Response:

Yes, the "that even the critics acknowledge" piece in the stimulus is doing important work here, but this is actually telling us that the critics do acknowledge the tremendous public support for the project (not that they're failing to acknowledge a lack of support). If we look at that full sentence ("If the critics were right about this, then there would not be the tremendous public support for the project that even its critics acknowledge"), we can glean that (a) tremendous public support for the project exists and (b) the critics acknowledge the existence of this public support.

Student Question:

I read the explanation and watched the video. I’m still confused about the “low average” in answer choice B. It seems like low average speed was a new concept and the stimulus talked about actual speeds and speed increases. I don’t see how support for low average speed. Please help. Thanks!

Tutor Response:

It's true that “low average speed” isn’t a phrase the stimulus uses, so it can feel like a new topic. However, it’s actually already in the argument implicitly, because the editorialist’s central warning is: if speed limits rise, average speeds will rise, and that will greatly decrease safety. That only makes sense if the author is assuming that having a lower average speed is important for safety (or at least more important than anything else that might change).

Answer choice B attacks that exact hidden assumption. To see this, let’s look at the author’s logic:

1. Raise the speed limit

2. Average speeds go up (because many law-abiders will drive faster)

3. Therefore safety goes way down

For step 3 to follow from step 2, the author has to be treating higher average speed itself as a big driver of danger—in other words, a low average speed is safer than a high average speed, all else equal.

B then gives us: “Uniformity of speeds among vehicles is more important for highway safety than is a low average highway speed.” In other words, even if average speed goes up, safety might not go down if raising the limit increases uniformity (i.e., reduces big speed differences between cars). And that’s a very plausible “all else isn’t equal” counterpoint: if everyone clusters around a similar speed (which the stimulus establishes raising the speed limit would likely lead to), we can get improved highway safety, even at a higher average speed.

Given this, B weakens the argument by showing that the author may be focusing on the wrong safety variable. The editorialist says “highway speed limits increasing → average speed increasing → safety decreasing” but B undercuts the idea that "average speed increasing → safety decreasing." Perhaps it's actually that highway speed limits increasing → average speed increasing AND greater speed uniformity → highway safety increasing overall.

A quick way to see the connection between the stimulus and B is that the stimulus is about average speeds (what happens to them if limits rise). B says average speed level is not the main thing—difference between the speeds of cars on the road is. That’s directly relevant, not a new concept.

Student Question:

Honestly, this question is just going right over my head. I really don’t know what I’m missing. It makes sense on paper, but I don’t get how to avoid having this happen in a future question.

Tutor Response:

The way I'd recommend trying to better understand this one and to approach future questions of these types is a two-part approach: (1) diagramming the stimulus's logical structure and (2) using a shallow dip analysis to evaluate how closely an answer choice matches up to that diagram.

This question is particularly tricky in that the stimulus has a number of variables and requires a high degree of comfort with diagramming rules. In mapping it out, we'll want to create a conditional chain that connects the relationships between the different variables:

Candidate → small-business owner (m)→ competent manager → skills

---

Candidate (m)→ skills

At this point, the specific content of the stimulus no longer matters, so we can simplify this (either mentally or by actually writing it out) to:

A → B (m)→ C → D

---

A (m)→ D

Now, we can do a shallow dip on each answer choice: read it one line at a time and after each line, quickly ask, “If this were the match, what would the next line have to do?”

Answer Choice B's first sentence gives us "Maddy's → fat-free". To be the right answer, we should also see a sentence along the lines of "Most fat-free menu items are [X]", then something that captures X→Z ("All X are Z", "If X, then Z", etc.). The second the logical structure ceases to line up with what we're looking for, we can move on to another answer choice.

In this case, B is the same diagram as the stimulus, just with new nouns:

A[Maddy's] → B[fat-free] (m)→ C[sugar-free] → D[low-calorie]

---

A[Maddy's] (m)→ D [low-calorie]

To tackle this type of difficulty on future Parallel / Parallel Flaw questions, I'd recommend not trying to understand each answer choice in full. Instead, (a) identify the quantifiers in the stimulus, (b) sketch a quick diagram, and then (c) do a shallow dip of each answer choice, starting with whichever appears to be the most promising, until you find one that both preserves the same quantifier pattern and the same direction of the arrows. If a choice has “some” where you need “most,” or it concludes “all” when your conclusion is “most,” or it reverses a relationship without negating both sides (i.e., says B→A where we're looking for A→B), you can ditch it immediately without overthinking.

Student Question:

I understand why D is correct because it most seriously undermines the argument. But doesn’t C also partly weaken the argument? The conclusion claims “this boulder was probably deposited here, hundreds of miles from its geological birthplace, by a glacier.” Since C says there were volcanic birthplaces closer than hundreds of miles away, doesn’t it weaken that aspect of the conclusion? If C partially weakens the argument, I’m confused because I thought JY taught us that for a weakening question, 4 of the answers will not weaken the argument at all and 1 answer choice will. Yet in this case it seems that two weaken the arg but one just does it stronger.

Tutor Response:

Regarding your broader question: it can be the case that one answer choice weakens the argument very slightly whereas another answer choice weakens it much more drastically (and similarly with strengthening questions). The test-writers always allow for this possibility by asking us which answer most strengthens or weakens the argument.

For the majority of questions, however, there is just one answer choice that has the desired effect (in this case, weakening), and the other answer choices either have no effect on the argument or have the opposite of the desired effect (i.e., they strengthen the argument). In the cases where a weakening question has two answers that both weaken the argument, one's impact will be far stronger (very severely weakening the argument) while the other has only a very slight impact.

In this case, I could see an argument for saying that C is slightly weakening one detail of the conclusion: the fact that the boulder was deposited "hundreds of miles" from its geological birthplace. However, the central element of the author's conclusion is that a glacier resulted in the rock's movement, and C doesn't weaken that explanation. For that reason, I'd hesitate to say that C undermines the author's conclusion itself. At the same time, even if we were to determine that it does so slightly, D would still be the correct answer as it much more dramatically undermines the conclusion, making it far more challenging to explain how southward-moving glaciers could have moved this boulder to its current location.

Student Question:

I chose E because I thought it showed how the author used "familiar" to describe the traditional way of thinking the author was alluding to in the second sentence.However, the correct answer seems to link "familiar" to "tiny bit dull" at the end of sentence? I'm not sure what I'm missing here.I get why B explains "tiny bit dull" but I don't understand how "familiar" comes into play there. Please help

Tutor Response:

The answer to this question doesn't actually hinge on the word "familiar"; what matters is the substance of that "familiar" view the author then goes on to name: the idea that, if a novel is enjoyable, then it's lowbrow, and unless a novel is a tiny bit dull, then it's not true literature.

Imagine if, instead of a "familiar" opposition, the passage read: "the opposition Professor Smith sets up between different kinds of fiction, according to which..." The question could then ask what best exemplifies "Professor Smith's attitude mentioned in the second sentence of the passage," and we could still approach and solve it in the exact same way. In other words, the word "familiar" isn't what's helping us identify the right answer choice; it's the characterization the author then provides as to what she means by the "familiar" view) that's giving us the real data.

Looking then at E, it is using one of the concepts the "familiar" view describes: an idea about what constitutes "true literature". However, the resemblance stops there: the author's description of the familiar view is that "if a novel is considered true literature, then it's a tiny bit dull". E is telling us "if a novel satisfies the requirements of its genre, then it's true literature". There are two significant differences between this and the author's description of the familiar view:

1. E is taking what the familiar view sets up as a sufficient condition (being true literature) and making it a necessary condition.

2. E is introducing a new concept (whether a novel satisfies the requirement of its genre) that the author's description of the familiar view doesn't consider, while ignoring the concept that the familiar view connects to being considered true literature: being a tiny bit dull.

Student Question:

Why is C wrong? If minivans tend to carry more passengers doesn’t that rule out an alternative ( which would strength?) explanation that the reason minivans have the lowest injuries per vehicle is that it carries less people?

Tutor Response:

The framework that you're using is right: for a strengthening question, a common pattern is that the correct answer choice eliminates a hypothesis that is a compelling alternative to the one the author proposes.

In this case, however, the author is arguing that a phenomenon (minivans' relative safety according to injury data, despite crash test results) is likely better explained by the drivers being lower-risk vs. minivans themselves being inherently safer. C is strengthening a separate idea (that minivans are the safest vehicles on the road), but it doesn't tip the scales one way or another regarding why that is: is it owing to the drivers (as the author contends) or to the vehicles themselves being safer (the alternative hypothesis)? As C doesn't provide any support for the author's explanation as opposed to the alternative, it's not the best answer here.

Student Question:

Since we only need to support that the proposed solution is a "viable" one, can (C) be incorrect because of the word "rarely"?

Tutor Response:

What we're looking for here isn't actually what most supports the author's solution. Instead, the right answer should be something that's necessary in order for the author's claim (that the proposed empty + refill midocean solution is a viable way of addressing the problem) to have a chance at being true. It's not the word “rarely” that makes C wrong in this case; C is wrong because it brings in an unnecessary claim about how often sea creatures wreck havoc in new habitats that is more general than the subset of situations the author's argument addresses.

The author is discussing a specific problem: sea creatures get into ships' tanks, end up being deposited in a new habitat when the ship unloads, and then wreak havoc in that new habitat. The author then makes a claim about a viable solution for this particular problem, but the argument doesn't address or care about other situations in which sea creatures wreak havoc separate from being carried to a new habitat by ships. As those situations aren't relevant to the author's argument, they can't be necessary for it, so answer choice C isn't what we're looking for.

Student Question:

I thought (E) was talking about an irrelevant timescope because of the word "are". Maybe we don't currently have these oceangoing ships whose stability can be maintained by emptying and refilling , but are currently under construction or can be easily built in the near future.

Tutor Response:

You’re right that right now not having ships that can safely do this wouldn’t prove it could never be done; maybe future ship designs could solve the stability issue.

But for this question, the key word in the stimulus is that the author calls it a “viable way” of addressing the problem. That’s stronger than “interesting in theory” or “might work someday.” To legitimately claim “viable,” the argument has to assume the plan is practically implementable with oceangoing ships.

Answer Choice E gives us the assumption the argument needs: At least some oceangoing ships can maintain adequate stability while emptying and refilling their ballast tanks in mid-ocean.

Part of the reason this is required is that the author never addresses the possibility of improving oceangoing ships to make mid-ocean empty/refill safe. If we try to answer your concern by saying “maybe they’re under construction” or “maybe they can be built soon,” we’re adding a new assumption the argument doesn’t give us. The argument needs something like E in place already (or at least as a realistic current capability) in order for “empty/refill in midocean” to count as a viable solution rather than a speculative idea.

If E were false—if no oceangoing ships could safely do this—then the proposal collapses: it might be a clever idea, but it wouldn’t be viable in the real world.

Student Question:

really need help, it never said that the two groups are comparable, it says these are the logical prediciton which is what I came up with “Dolphins can stay submerged longer than northern fur seals can. Elephant seals can dive to greater depths than Weddell seals can.

now tell me how this is the right answer choice D; Northern fur seals can stay submerged longer than elephant seals can, but Weddell seals can dive to greater depths than dolphins can.

we never made the comprison why cant it be that elephant seals cant stay submered longer than northern furs seals, this one i cannot see how its wrong, im lost

Tutor Response:

You're right to notice the stimulus establishes a correlation between longer submersion time and greater depth able to reach. This correlation is established as accurate for certain mammals including both seals and dolphins. We're then given four animal types that fall within these groups: Dolphins (D), Northern Fur Seals (N), Elephant Seals (E), and Weddell Seals (W).

To better visualize the connections here, we can plot the information we know on a spectrum from "Shorter submersion time + less depth able to reach" on the left side and "Longer time + further depth able to reach" on the right side.

The stimulus establishes:

1. N ---- D (D can be submerged longer + dive to greater depths than N)

2. W ---- E (E can be submerged longer + dive to greater depths than W)

Where I think the confusion is coming in is what's happening in answer choice D. This answer choice gives us two additional datapoints:

3. E ---- N

4. D ---- W

We can combine these facts with what the stimulus establishes. We get:

1 + 3: E ---- N ---- D

2 + 4: D ---- W ---- E

We have a shared variable here (D), so we can combine these to arrive at:

E ---- N ---- D ---- W ---- E

One part of this doesn't add up: E --- D ---- E. This is effectively saying "Elephant seals can dive to greater depths and stay submerged longer than dolphins, but dolphins can dive to greater depths and stay submerged longer than elephant seals". We've got a logical contradiction: both of these statements cannot be true at the same time! This contradiction means that, if we assume the facts in the stimulus to be true, answer choice D must be false.

Student Question:

The explanation for (C) relies on an unsubstantiated interpretation of the subtraction theory, as Al_foroodian's Sept. 01, 2025 comment explains well. Their comment also gives a better way to arrive at why (C) is the correct answer, without using this unsupported way of understanding the subtraction method. I wanted to bring this to 7Sage’s attention to consider updating the written explanation for (C) if you agree! Thanks for reading.

Tutor Response:

I’ll try to provide an alternative explanation for why C is most strongly supported, taking into account the analysis in the comment you mentioned.

The author of the passage explains that fMRI is “usually interpreted as a map of the rate of oxygen use in different parts of the brain, which stands as a measure of metabolic activity”. They then clarify that “what [the fMRI] actually depicts is the differential rate of oxygen use”. In my reading, then, this differential rate of oxygen use is what is actually serving as the measure of metabolic activity.

I do think that the passage’s discussion of the subtraction method is helpful in providing support for C. The passage points out that brain scans do, in fact, show well-defined areas that “light up” during various cognitive tasks, and it clarifies what that “lighting up” consists of: the scan is produced by taking an oxygen-use measurement at baseline, taking another while the subject performs a task, and subtracting the baseline from the on-task measurement. Whatever remains after subtraction is taken to represent the oxygen-use difference associated with doing the task, which is why certain regions appear more active than others in the final image.

This method of calculation provides support for the statement in C that, during some cognitive tasks, the areas that are most metabolically active show a higher rate of oxygen use than the rest of the brain: “most metabolically active” lines up with “oxygen use” as the proxy for metabolic activity, and “higher than the rest of the brain” matches the idea that some regions show a larger oxygen-use difference when the task is being performed.

A broader element that helps to justify C is that the passage doesn’t need to establish or imply with certainty that C is true. For it to be the correct answer here, it just needs to be more strongly supported than any of the other answer choices (vs. if this were a Must Be True question). In a situation like this passage where one point of ambiguity seems to be the specific metrics that are being used in the fMRI “subtraction method”, if a reasonable interpretation of the statements in the passage supports C, and no other answer choice is supported, we can conclude C is the correct answer, even if it doesn’t follow from the statements in the passage with 100% certainty.