A recent poll showed that almost half of the city’s residents believe

Previously, <= 52% believed that the Mayor was good/excellent. (so about 50% thought he was not good)
Ethics violation accusation happened.
Almost 50% people believe the accusation that Mayor is guilty.
Still 52% believe that the Mayor is good/excellent.

What helps explain this?

(A) Almost all of the people who believe that Walker is guilty of ethics violations had thought, even before he was accused of those violations, that his performance as mayor was poor.

All who believe the Mayor is guilty had thought that the mayor was poor before the accusations. So the 50% who believe that the Mayor is guilty had anyway given him a poor rating previously too. So the other 50% who believe that he is not guilty though he was good/excellent.
Since this other 50% anyway doesn't believe the accusation, they did not change their mind. Hence the percentage who believe that the Mayor is good/excellent did not change by the accusation. Correct.

(B) In the time since Walker was accused of ethics violations, there has been an increase in the percentage of city residents who judge the performance of Walker’s political opponents to be good or excellent.

How the residents judge the performance of the opponents is irrelevant.

(C) About a fifth of those polled did not know that Walker had been accused of ethics violations.

Only a fifth did not know about the accusation. The rest 4/5th did know. Still the percentage did not decrease at all. This option does not explain that there was no decrease.

(D) Walker is currently up for reelection, and anticorruption groups in the city have expressed support for Walker’s opponent.

Irrelevant. It doesn't tell us why the percentage has not decreased.

(E) Walker has defended himself against the accusations by arguing that the alleged ethics violations were the result of honest mistakes by his staff members.

It doesn't matter how he has defended himself. We already know that 50% believe he is guilty.

Answer (A)

VeritasKarishma

Nice explanation for why E is incorrect.

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