This answer choice erroneously contraposes a “most” statement like a normal conditional statement. The author’s premise doesn’t imply that people not in the second set (believing in reduced fire risk) are also not members of the first (supporting limited logging). Also, the author states that most in the first set belong to the second set without elaborating on the opinions of the minority of that first set. Those in the first set, but not in the second set, potentially like Andy, could have different reasons for supporting limited logging.

Wrong flaw. This answer choice confuses its necessary and sufficient conditions. It defines knowing a person expects a population increase as sufficient to know that most of the time, that person also thinks a new school should be built. This answer choice then negates its sufficient condition and draws a conclusion of a negated necessary condition, whereas the stimulus erroneously contraposed its “most” statement and made a mistake in its set logic.

Wrong flaw. This answer choice confuses its necessary and sufficient conditions. In the premises, it defines knowing a person believes the economy has improved as sufficient to know that most of the time, that person also thinks their own financial situation has improved. This answer choice then negates its sufficient condition and draws a conclusion of a negated necessary condition, whereas the stimulus erroneously contraposed its “most” statement and made a mistake in its set logic.

No flaw. The author defines Donna as someone who fulfills the sufficient condition for their statement that most of the people who oppose funding the study also think the Valley Freeway should be built. Saying that she “probably” fulfills the necessary conclusion in the conclusion is supported because the “most” statement shows that more likely than not, Donna also agrees with funding the freeway.

No flaw. The author defines Eduardo as someone who fulfills the sufficient condition for their statement that most of the people that think there will be a blizzard tomorrow think this because they saw the Channel 9 weather report. Saying that he “probably” fulfills the necessary condition in the conclusion is supported because the “most” statement shows that more likely than not, Eduardo has seen the Channel 9 report.