The first response is the only claim that makes sense. To check, let's use the process of elimination.
Second: Calling the scientists' surveys unsophisticated is irrelevant and does not prove that the original claim is correct.
Third: This option does not address the points made by the counterclaim and instead pushes the original idea. It is important to remember that it is supposed to be a response, not a new statement.
Fourth: This response gives up on the original idea and ends the debate, with the counterclaim winning.
The answer is B. Fredrick Douglass never describes his means of escape. He didn't want to disclose the information because he didn't want slaveholders to know how he or any other slave could have escaped.