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

Only the right answer will finish the conclusion with an accurate description of what these two disagree about.

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

Bernard: We should not invite Carl to speak the at the forum.

Ayla: Once Carl’s views are subjected to the kind of public scrutiny the forum provides, people will see them for what they are

Bernard: [MAIN CONCLUSION]. [SUPPORT]. [SUPPORT], [INTERMEDIATE CONCLUSION], since [SUPPORT].

Ayla: [SUPPORT]. [CONCLUSION]. because [SUPPORT].

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

(A) one should always avoid legitimizing…

Too strong. Both arguments are focused on only one case, and Bernard only talks about that case specifically.

(B) people will see the falsity of every dangerous idea…

Too strong, since clearly neither gives a take on what happens in “every” case.

(C) the best way to fight erroneous ideas…

As long as you know “erroneous” means “false”, this all checks out. This maps perfectly to Ayla’s conclusion. And Bernard must disagree that’s the best way, since he’s suggesting a different way.

(D) …tend to pose a danger to society

This is too broad to map to Bernard’s statement that was just about “Carl”, and Ayla never got into “danger to society”.

(E) one should not encourage the adoption of dangerous views

This is also too broad to fit arguments centered on just one example, but I also think it’s fair to guess these two would actually agree on this one.

(C) is the correct answer.