Q7 - Dietitian: Eating fish can lower one's

[mshinners]

Question Type:
Determine the Function

Stimulus Breakdown:
Since the first sentence is followed up by "In a study", I'm reasonably certain it's the conclusion, and this study will form the premises. Reading through the rest, it's what I expect from a study - they looked at two groups and compared them. The last statement is the one in question, and it tells me something specific about the groups.

Answer Anticipation:
What does it tell me? That these two groups were similar in a relevant way before the study. This statement essentially says that the study eliminated at least one source of Sampling error - starting with groups that are different in the key metric (cholesterol levels).

Correct answer:
(C)

Answer choice analysis:
(A) Opposite. The statement is a premise that helps argue for the validity of the study used by the dietitian to reach her conclusion.

(B) Wrong function. The first statement uses the study to justify itself, so that's the conclusion. Additionally, the last statement is very fact-y (one could simply measure the levels, no argument needed), and those tend to be premises.

(C) Bingo. The last statement rules out one type of sampling error (the groups started off different in the relevant measure).

(D) Tempting - this definitely provides background information. However, that background information isn't about the purpose of the study. This answer refers to a hypothetical statement saying, "Cholesterol levels are related to heart disease, which kills more people every year than any other cause, so reducing them would be impactful and lucrative."

(E) Opposite. Notice the similarity between this and (C). The statement in question rules out an alternative explanation; it doesn't introduce it. It's also an alternative explanation for the results of the study, not for the main conclusion (which is specifically about fish).

Takeaway/Pattern:
The LSAT is increasingly using ideas from ID the Flaw questions in the Argument Structure family. Here, knowledge of Sampling flaws could have helped answer this question.

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