PTF97 S3 Q16 - Zebra mussels a nusiance. MSS Question

riosandronicus88

Hi All,

This is my first post, so if I make any major "faux pas", please let me know. This post is regarding a MSS question on PT Feb 1997, Section 3, Question 16.

In this question stimulus, we are given a discussion about zebra mussels—an invasive species in the Great Lakes that possesses some redeeming qualities. Zebra mussels consume algae that they filter from the water, and in discharge streams, they improve water quality by removing some amounts of hazardous waste.
Question stem: Which one of the following is most strongly supported on the basis of the statements above, if they are true?
Responses:
(A). Zebra mussels arrived on transatlantic freighters, and displace native species.
A is incorrect. This is because it is irrelevant how or why the Zebra mussels are here. We want to know what the implications of their redeeming qualities and presence in the lakes means for the chemical plant.
(B). If Zebra mussels spread to the Mississippi River, the clam industry will collapse.
B is incorrect. This response is irrelevant, we simply don't have any information in the passage to show that the Mississippi River clam industry will collapse. Also, we aren't really interested in this information either.
(C). There is no mechanical means of clearing the Zebra mussels.
C is incorrect. This response is irrelevant and is not supported by the passage. There very well could be mechanical means or other means of clearing the Zebra mussels.

After reviewing all of the answers, I was down to the final two responses:
(D). The algae on which the mussels feed would, if not consumed by the mussels, would clog the intake pipes at the chemical plants.
D This answer is incorrect. I anticipated that this statement is the most strongly supported. Based on my initial reading, it seemed like this would be a logical inference to make. The algae would likely clog the intake pipes, BUT FOR the zebra mussels consuming them.
Do we not have enough information from the passage to support this answer?

(E). Any hazardous waste the mussels remove from the chemical plant will remain in the mussels, if they do not transform it, they must be regarded as hazardous waste.
Answer (E) is the correct answer. This answer is the most strongly supported response. This answer is somewhat sensible, but it still seems a bit off. How do we know that the hazardous waste will go into the mussels? The last clause of the sentence makes sense "if they do not transform it, they (the mussels) must be regarded as hazardous waste". However, for this to be true, we must accept the first clause of the sentence, which I don't think we currently have enough support in the passage to make.

Note: This is the major curve-breaking response, and is likely a major source of error/frustration for many. I am one of the frustrated ones. In short, I am still a bit confused on why E is correct, rather than D. Answer E simply sounded a bit too a dystopian Sci-Fi of a response to be correct.

I would appreciate any feedback that you folks have to offer. Thanks.

dhommy24

E. Any hazardous waste the mussels remove from chemical-plant discharge will remain in the mussels, if they do not transform it, and they then must be regarded as hazardous waste.

It looks like your confusion stems from assigning the "if they do not transform it" bit to the final clause of the sentence. I did the same thing upon my first reading. But it makes more sense to associate that middle bit with the first clause. This is because of the sneaky little "and... then" breaking apart the AC.

Another way to read this AC would be: "If they [the mussels] do not transform it, any hazardous waste the mussels remove from chemical plant discharge will remain in the mussels,............ and they then must be regarded as hazardous waste."

The rephrased AC makes some intuitive sense. Obviously, hazardous waste, if not transformed, is still hazardous waste. Even if it's just hanging out inside a mussel. And yeah, mussels full of hazardous waste should probably be regarded as hazardous waste themselves.

How do we know the hazardous waste will go into the mussels?

Check out this premise from the stimulus: "Since the mussels feed voraciously on algae... bags of zebra mussels... significantly improve water quality, even removing some hazardous waste." In other words, the mussels remove the waste because they eat the algae. And per the almighty question stem, this part must be true.

[W]e must accept the first clause of the sentence, which I don't think we currently have enough support in the passage to make.

Ok, so, taking a look at the first clause: "Any hazardous waste the mussels remove from chemical-plant discharge will remain in the mussels..."

Does the passage support this idea?

Kinda, yeah! We know the mussels remove some waste. That part is explicitly stated. If the mussels were to then release the hazardous waste, untransformed, back into the water, they wouldn't really be doing a good job of removing waste, would they?

Sure, so the mussels remove "some" of the waste. But what if they excrete a little of what they ate back into the water? That way the waste is still mostly, or perhaps temporarily, removed, the stimulus isn't violated per se, and AC E wouldn't seem so strong.

You're right. We kinda have to assume that that doesn't happen. But there's good reason for doing so. Simply put, the LSAT means what it means. In other words, each word is chosen carefully, and should be taken seriously. When the LSAT overlords wrote "even removing some hazardous waste," they meant removing. If the removal was temporary, they likely would have said so somehow. I catch myself making arguments like this one--arguments that turn on questioning the face value of a given word--all the time. Very very rarely do these arguments lead to the correct AC.

As for AC D, do we know that the algae clogs the pipes? Sure, the mussels can --and do-- clog the pipes, which part of the reason why they suck. But in order for D to make sense, we have to assume that, were it not for the mussels, the algae would be clogging the pipes.

That notion isn't mentioned in the stimulus... Is that a safe assumption to make? Maybe, I guess it depends on how much you know about algae. But, regardless, which of our above assumptions is easier to swallow? Assuming that algae can and would clog the pipes were it not for the mussels? Or assuming that when the LSAT writers said "removing" they deceptively meant "removing temporarily?"

The LSAT writers are sneaky to be sure, but liars and deceivers they are not.

riosandronicus88

Thank you so much for your detailed analysis and response to my questions. I appreciate how you discuss what kinds of assumptions are warranted when taking the test and reading the stimulus. We should really bracket our assumptions and focus on the material presented in the stimulus and in the responses.

"The LSAT writers are sneaky to be sure, but liars and deceivers they are not." This final sentence really hit home. I will keep this notion in mind as I continue to take practice problems and tests.

Thanks again for your amazing reply.