How will the right answer fit in terms of support and conclusion?

Only the right answer will accurately describe the support and conclusion.

Highlight the main conclusion in the passage, if there is one:

the attendance problem was not due to primarily schedule conflicts.

[BACKGROUND]. [BACKGROUND]. [SUPPORT]. On the basis of this survey result, the club’s president concluded that [CONCLUSION].

Map the wording of the answers to the wording of the passage:

(A) …on the basis of circular reasoning

You only have “circular reasoning” when the support and conclusion are the same. Something like, “You’ll get at least a 170 on the LSAT, because you won’t score lower than 170.” This flaw is extremely rare on the LSAT, but it’s a fairly common wrong answer.

(B) …on the basis of a sample that is likely to be unrepresentative

The club president’s sample only included people who were there on a Tuesday, so naturally the results indicated that everybody can make it on Tuesday. Of course they should’ve asked people who can’t make it on Tuesday also. That’s pretty much the definition of “unrepresentative”.

(C) …a generalization that applies to most cases…

The only “generalization” is the conclusion about what’s causing “the attendance problem”. That’s only one case, so “applies to most cases” doesn’t map to anything in the passage.

(D) …premises that contradict one another

The club president doesn’t “contradict” themselves anywhere. That would mean two premises can’t possibly both be true, not just that they conflict somewhat.

(E) …the claim that a change is not sufficient to solve a problem…

Where do you see that claim in the passage? Me neither. It’s not there. The club president never says changing the schedule isn’t good enough. You can’t assume that just because they said the schedule isn’t the cause of the attendance problem.

(B) is the correct answer.