Answer Choice D

Hi @DavidW, Thanks for the question! For where you can find answer choice (D) in the first paragraph, take a look at the last paragraph, where the example of a pathological, but harmless, liar is brought up. The author then applies the idea of forfeiture to this harmless pathological liar, concluding that “his tall tales would not constitute sufficient reason to lie to him” (lines 23-24). Here, in other words, the author is suggesting that the idea of forfeiture can have unreasonable consequences. 
 As for the instantiation of (D) in the second paragraph, take a look at lines 38-46. The author is talking about Kantian universalization, and then applies it to the idea of having “a duty to do to all rational persons everything…that they do to others,” which the author thinks is unreasonable. Hope this helps! Feel free to ask any further questions that you might have.

Why is A wrong?