The answer is A.

We can solve this question using the

Logical

approach, because it is all about correlation and causation.
We are told there is a positive correlation between two factors (the tax hike and the drop in ratings), and Jones wants to claim there is no causation. Let's remember, then, in what ways correlation can not imply causation: causation can be the opposite (the drop in ratings caused the tax hike somehow), it can be a coincidence, or there can be a third factor which causes both. (A) fits this last case, because it tells us the drop in ratings happened in other places as well: thus, the tax hike was not the cause, but presumably some more general factor.
A. All elected officials in his area experienced similar drops in approval numbers at the same time.

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Congressman Jones experienced a drop in his approval numbers after announcing that taxes in his district would increase the following year. His office also received a significant number of phone calls decrying this tax raise. Nevertheless, he claims that reactions to the tax increase were unrelated to his drop in voters' approval of him.

Type - Strengthen
Boil it down - he claims that reactions to the tax increase were unrelated to his drop in voters' approval of him.

A. All elected officials in his area experienced similar drops in approval numbers at the same time. -- Correct -- So the cause of the drop in approval numbers was something else

B. The citizens who called in to Congressman Jones's office had all voted for him in the previous election. -- Irrelevant

C. Elected officials are only likely to attribute drops in their approval numbers to policies only when citizens call their offices about these policies. -- Irrelevant

D. Congressman Jones previously raised taxes in his district and received a similar number of phone calls.-- Incorrect -- it is weakener

E. Most voters in Congressman Jones's district list taxes as their number-one household expense. -- Irrelevant -- this only tells us that increase in taxes will impact the residents of the district

Answer A
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Congressman Jones experienced a drop in his approval numbers after announcing that taxes in his district would increase the following year. His office also received a significant number of phone calls decrying this tax raise. Nevertheless, he claims that reactions to the tax increase were unrelated to his drop in voters' approval of him.

Type - Strengthen
BID - author says drop in voters not because of his tax increasing plans
Missing info:1)some other reason for drop
2)the two things a not related but coincidental

looking at the answer choices

A. All elected officials in his area experienced similar drops in approval numbers at the same time. : hold On :if all numbers are falling then the events are not related (our missing gap no 2)

B. The citizens who called in to Congressman Jones's office had all voted for him in the previous election. so what :no effect on numbers falling
C. Elected officials are only likely to attribute drops in their approval numbers to policies only when citizens call their offices about these policies. aftermath of the drop is irrelevant we are interested in the cause

D. Congressman Jones previously raised taxes in his district and received a similar number of phone calls.: a previous incident doesnt warrant it will be true this time

E. Most voters in Congressman Jones's district list taxes as their number-one household expense. :so what : we are interested with cause of the drop


only A stands and the correct answer

Official Explanation
Answer = (A).

Two things happened at the same time: the Congressman’s approval numbers dropped and he received phone calls about the tax raise. The Congressman claims that these two things aren’t related—in other words, just because they happened at the same time, it does not mean that one caused the other. To strengthen his argument, we need to find evidence of another cause for at least one of these events. (A) gives us that: if all elected officials experienced a drop in approval numbers, there may have been some kind of a scandal, or simply increasing disillusionment with politicians in the area.

Even if the citizens who called had voted for Congressman Jones (B), this doesn’t provide an alternate explanation for either the sinking approval numbers or the increase in phone calls. If they hadn’t voted for him, that might make more sense, but it still wouldn’t strengthen the Congressman’s position.

(C) claims that politicians WOULD correlate the phone calls and the approval numbers, which Congressman Jones is not doing. Therefore, we can see that this might be a weakener, but it’s definitely not a strengthener.

(D) suggests that there is a connection between raising taxes and the number of phone calls he receives, which would weaken Congressman Jones’s argument. Furthermore, it doesn’t account for the lower approval rating, either.

While it doesn’t sound pleasant to live in Congressman Jones’s district and pay such high taxes (E), this doesn’t make it more likely that the approval numbers and phone calls are unrelated, which is Congressman Jones’s position.
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Congressman Jones experienced a drop in his approval numbers after announcing that taxes in his district would increase the following year. His office also received a significant number of phone calls decrying this tax raise. Nevertheless, he claims that reactions to the tax increase were unrelated to his drop in voters' approval of him.

Which of the following, if true, most strongly supports Congressman Jones's position?

Stated Facts:
1) Drop in approval ratings coincided with the announcement of increase in taxes
2) His office received phone calls decrying tax raise

Congressman Jones's position: The announcement of increase in taxes is not a cause for the drop in approval numbers

Nature of the statement that supports Congressman Jones's position:
1) Gives an alternative cause for the drop in the approval numbers
2) Show that these two things were not co-related


A. All elected officials in his area experienced similar drops in approval numbers at the same time. - Correct
Shows that the two were not co-related and thus support Congressman's position

B. The citizens who called in to Congressman Jones's office had all voted for him in the previous election. - Incorrect
This in fact shows that people who once supported him are not happy with his recent tax raise announcement, this statement actually slightly weakens Congressman's position

C. Elected officials are only likely to attribute drops in their approval numbers to policies only when citizens call their offices about these policies. - Incorrect
This statement states that the elected officials are attributing the drop to the policy and doesn't give an alternate causation

D. Congressman Jones previously raised taxes in his district and received a similar number of phone calls. - Incorrect
This talks about the past and doesn't talk about alternate causation

E. Most voters in Congressman Jones's district list taxes as their number-one household expense. - Incorrect
This actually gives the reason for the resentment among voters and weakens the Congressman's position.