Hi!
First of all, you are absolutely correct in your approach to answer selection for this problem. When analyzing the argument, we need to identify the paradox, and know that the correct answer will allow both sides of the paradox to remain true.
With that in mind, here's my take on the problem:
Experiment Setup:
First round-- lawyer tries to make folks answer inaccurately
Second round -- lawyer tries to make folks answer accurately ("correct inaccuracies")
Experiment Results:
First round -- some witnesses gave relatively accurate testimony
Second round -- those same witnesses gave relatively inaccurate testimony
We simply need an answer choice that offers a reason why some people performed completely opposite to the way the questioners were trying to make them perform.
(A) helps explain why some people were more accurate during the first round, but offers no explanation about those people's performance in the second round
(B) same as (A)
(C) says that the people in question weren't influenced by the questioners. this would provide a possible explanation for the contradictory results of the experiment.
(D) says that answers became more accurate over time, but this is the opposite of what happened
(E) more details? hmm. a somewhat tempting answer at first, but actually doesn't help. That they provided more details does not explain why the volunteers in question were the most accurate at first and then most inaccurate under cross-examination.
(C) is the best answer. Compared with the rest of the answer choices, it "most" helps to resolve the paradox at hand. Resist the temptation to get tangled up in wondering why their answers seem to have become less accurate over time -- that's a trap. The real paradox is that their behavior was contrary to the experimenters' intentions, and (C) DOES explain why this is so.
If you're still confused, consider this: what if the experimenters had designed things like this:
First round -- lawyer tries to make answers accurate
Second round -- lawyer tries to make answers inaccurate
Then the results are the same. Is it still weird that their answers got less accurate over time? A little bit, yes. One would think that a person's answers would have a consistent level of accuracy/inaccuracy. But is there a paradox to explain? No. They were being influenced by the lawyers, just as intended.
Hope that helps!
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