详解
Choice A is the best answer. In lines 4-5("Some...ethical"), the author states that some people believe that free markets are"already ethical"because they "allow for personal choice." This statement provides evidence that some people believe criticizing the ethics of free markets is unnecessary because free markets permit individuals to make their own choices.
Choices B, C, and D are incorrect because they do not provide the best evidence of an objection to a critique of the ethics of free markets.