We start with the question stem: Which of the following most accurately expresses the overall conclusion drawn in the argument? This is a Main Conclusion question.

The author begins by saying that scientists were studying a particular bacteria and that most of that particular type of bacteria are in hibernation at any given moment. So we have a type of bacteria called 'X.' You'll find that more than half of them are in hibernation. OK. The author says that some microbiologists have concluded that bacteria, in general, are usually in hibernation.

The author goes on to say that "this conclusion (that bacteria are usually in hibernation) would be reasonable if all types of bacteria were similar)." The author is saying, "Hey. If 'X' is usually in hibernation and all bacteria were similar to 'X,' then it wouldn't be so crazy to think that all bacteria were usually in hibernation." OK, author, I don't hate where you are going with this. She then says, "but (OK, we are turning to her argument), in fact, since (premise indicator) they (the bacteria) are extremely diverse, "it is unlikely that most types of bacteria hibernate regularly (conclusion)." We have our Main Conclusion.

At this point, on the test, you would go and hunt for that in the answer choices. As good 7Sage students, you likely recognize that the author's argument is quite poor. But our job here is not to evaluate. Our job is to find the Main Conclusion (which we have), and look for a paraphrase of it in the answer choices.

Answer Choice (A) is not the author's MC. We do not even know if this is the microbiologists' conclusion. Those microbiologists claimed that bacteria, in general, are usually in hibernation. Imagine that a single bacteria strain out of 100 makes up 99% of bacteria and that bacteria is always in hibernation. The other 99 types are not hibernating. In that case, "bacteria in general" are in hibernation, but only 1% of the types of bacteria are in hibernation. Either way, not our Main Conclusion.

Correct Answer Choice (B) is a paraphrase of our Main Conclusion. The author used the term "unlikely," while (B) uses "probably not true." These terms are interchangeable.

Answer Choice (C) is tempting, but if you picked this answer, either you failed to notice the premise indicator "since," or you were trying to fix the argument. (C) would fix the argument. It is the most basic form of a Sufficient Assumption: If Premise, then Conclusion. But our job is to find the Main Conclusion, not to make the argument valid.

Answer Choice (D) is a claim the author makes, but she offers no support for it. Therefore, this is not our main conclusion. She actually uses this claim to introduce her argument.

Answer Choice (E) is too specific. The author does not attempt to show how many bacteria hibernate regularly; she simply wants to say it is unlikely most types of bacteria hibernate regularly.


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In her recent book a psychologist described several cases that exhibit the following pattern: A child, denied something by its parent, initiates problematic behavior such as screaming; the behavior escalates until finally the exasperated parent acquiesces to the child’s demand. At this point the child, having obtained the desired goal, stops the problematic behavior, to the parent’s relief. This self-reinforcing pattern of misbehavior and accommodation is repeated with steadily increasing levels of misbehavior by the child.

Summary
In some cases when a child does not get what they want from a parent, they display problematic behavior. The behavior escalates until the parent gives in to the child’s demand. When the parent gives in, the child stops their misbehavior. This reinforcing pattern of misbehavior and accommodation is repeated with increasing levels of problematic behavior by the child.

Strongly Supported Conclusions
We should note that, since this is an “except” question, any strongly supported conclusion will be an incorrect answer choice. We’re looking for an answer choice that is unsupported or least supported. Some strongly supported conclusions can include:
Some children adopt problematic behaviors as a result of getting what they want.
Some child and parent relationships mutually influence each other’s behavior.
Some parents unintentionally cause their children’s problematic behavior.

A
A child can develop problematic behavior patterns as a result of getting what it wants.
The stimulus tells us that getting what they want is a direct cause of problematic patterns of behavior.
B
A child and parent can mutually influence each other’s behavior.
The parent is influencing the child’s behavior by giving in, and the child is influencing the parent’s behavior by misbehaving.
C
Parents, by their choices, can inadvertently increase their child’s level of misbehavior.
The parent could inadvertently cause problematic behavior by giving in to the child’s demands.
D
A child can unintentionally influence a parent’s behavior in ways contrary to the child’s intended goals.
The influenced behavior by the parent is not contrary to the child’s goals. In the stimulus, we’re told that the parent’s behavior results in the child getting what they want.
E
A child can get what it wants by doing what its parent doesn’t want it to do.
The child gets what they want from the parent through problematic behavior. Certainly the parent does not want the child to display problematic behavior.

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Scientist: In our study, chemical R did not cause cancer in laboratory rats. But we cannot conclude from this that chemical R is safe for humans. After all, many substances known to be carcinogenic to humans cause no cancer in rats; this is probably because some carcinogens cause cancer only via long-term exposure and rats are short lived.

Summarize Argument
The fact that chemical R did not cause cancer in rats does not mean chemical R is safe for humans. Many substances cause cancer in humans but not rats. This likely because some substances cause cancer through long term exposure and rats live short lives.

Identify Argument Part
This is context that sets up the argument. The conclusion refers to this context when it says: we cannot conclude from “this.” The stimulus is arguing that this piece of information is not enough to draw a conclusion.

A
It is cited as evidence against the conclusion that chemical R is safe for humans.
It is not evidence, and no conclusion is being drawn that chemical R is safe.
B
It is advanced to support the contention that test results obtained from laboratory rats cannot be extrapolated to humans.
This is not used to support that extrapolation cannot occur, or anything else. We are told that this information is not sufficient to draw a conclusion about humans.
C
It illustrates the claim that rats are too short lived to be suitable as test subjects for the carcinogenic properties of substances to which humans are chronically exposed.
While this describes a feature in the later part of the argument, the text in question does not illustrate this claim. It is just context.
D
It is used as evidence to support the hypothesis that chemical R causes cancer in humans via long-term exposure.
The conclusion being drawn is that this statement is not enough to say the chemical is safe for humans. No hypotheses are formed about how chemical R might cause cancer.
E
It is cited as being insufficient to support the conclusion that chemical R is safe for humans.
The conclusion is that “we cannot conclude from this (the text in question) that chemical R is safe for humans.” The argument tells us that this statement is not enough to draw that conclusion.

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Among people who have a history of chronic trouble falling asleep, some rely only on sleeping pills to help them fall asleep, and others practice behavior modification techniques and do not take sleeping pills. Those who rely only on behavior modification fall asleep more quickly than do those who rely only on sleeping pills, so behavior modification is more effective than are sleeping pills in helping people to fall asleep.

Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that behavior modification techniques are more effective than sleeping pills for helping people fall asleep. She bases this on the observation that, among people who chronically struggle to fall asleep, people who use behavior modification techniques fall asleep quicker than people who use sleeping pills.

Notable Assumptions
Based on relative correlations between the techniques (behavior modifications, sleep pills) and falling asleep, the author hypothesizes that one technique is more effective than the other. This means the author assumes that all other variables—e.g. severity of insomnia, mental health, medical status—are constant between the two groups of people who chronically struggle to fall asleep.

A
People who do not take sleeping pills spend at least as many total hours asleep each night as do the people who take sleeping pills.
We don’t care how long people stay asleep for. We’re interested in how easily they fall asleep, and whether any conclusions about different techniques can be drawn from the author’s data.
B
Most people who have trouble falling asleep and who use behavior modification techniques fall asleep more slowly than do most people who have no trouble falling asleep.
We’re not comparing against people who don’t have trouble falling asleep. Of course those people have an easier time.
C
Many people who use only behavior modification techniques to help them fall asleep have never used sleeping pills.
It doesn’t matter if these people have ever tried sleeping pills. We only care about the relative efficacy of the two techniques.
D
The people who are the most likely to take sleeping pills rather than practice behavior modification techniques are those who have previously had the most trouble falling asleep.
The two groups in question aren’t in all respects equal. People who use sleeping pills have had more difficulty falling asleep than people who use behavior modification techniques. Thus, no conclusion can be drawn about the efficacy of the techniques.
E
The people who are the most likely to practice behavior modification techniques rather than take sleeping pills are those who prefer not to use drugs if other treatments are available.
This isn’t a significant difference between the groups. Maybe people using behavior modification techniques didn’t want to use sleeping pills. But that doesn’t mean they wouldn’t have derived the same benefit from those pills as from the behavior modification techniques.

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The Question Stem reads: The lawyer's conclusion follows logically if which one of the following is assumed? This is a Sufficient Assumption question.

The lawyer begins by describing how this witness was present at the restaurant when the lawyer's famous client was assaulted. However, the witness claims to recognize the assailant but not the famous client. The lawyer concludes the witness's testimony should be excluded. We can break down the argument to read:

P1: Witness claims to recognize the assailant

P2: Witness claims not to recognize the victim (Famous client)

________________

C: Exclude witness testimony

In the CC, we discussed that elements of the conclusion must be in the premises. Nowhere in the premises do we see a claim about what kind of testimony should not be included. We need a conditional that brings us to "exclude testimony," so let's make that our necessary condition: (__) -> Exclude testimony.

Now it will be hard to anticipate what sufficient condition the AC will use. They could use P1 or P2 or some combination of both. When we screen these answer choices, the first order of business will be to make sure that the necessary condition is: "exclude testimony" Then we will check the sufficient condition to ensure it gets triggered by the information in the stimulus. Let's go.

Answer Choice (A) has the necessary condition "then the witness's testimony should be included." Without looking at the rest of the (A), we can eliminate it because it takes us to "include" when we want to go to "exclude." If you picked (A), you likely assumed that "claims recognize both parties -> include" implied that "/(claims recognize both parties) -> exclude," which is a logical fallacy. Remember: a->b does not imply /a->/b.

Answer Choice (B) is arbitrary. Why would the fact that other witnesses can identify the client mean we should exclude the witness from the stimulus? Nothing. Eliminate and move on.

Answer Choice (C) is also arbitrary because it does not bring us to a conclusion "exclude testimony." As a side note, whether or not we can know if the witness actually recognized the assailant is irrelevant. Notice how the premises only take into account who the victim claims to recognize. The lawyer's argument is going to rely on the witness's claims, not what actually is the case.

Correct Answer Choice (D) gets us to where we need to go. If we take the contrapositive of (D), we get: "/(claims to recognize both parties in assault) -> exclude." The necessary condition is exactly what we discussed. The sufficient condition is great. The witness did not claim to recognize both parties in the assault. The witness claims to recognize only the assailant. So the conditional triggers and delivers us to the conclusion that the witness's testimony should be excluded.

Answer Choice (E) is a popular wrong answer. If you picked (E), you likely inferred that the witness was lying about not recognizing the famous victim. First, that is not an inference you can make. Just because it is unlikely that someone wouldn't recognize the famous client, that does not mean it is impossible that someone would fail to recognize the client. Second, even if we could infer that the witness was lying, it wouldn't help us. What does lying have to do with excluding testimony? If you answered that "liars testimony should be excluded," you've proved that (E) by itself is insufficient to draw the lawyer's argument.


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