With diamonds, as with all gems, one should ask for a written description of one’s purchase; the description may prove useful later if you have reason to believe the jeweler misled you.

(A) one should ask for a written description of one’s purchase

(B) you should ask for a written description of your purchase

(C) a written discretion of your purchase is what one should ask for

(D) a written description of one’s purchase is what should be asked for（B）

(E) a written description of your purchase is what should be asked for

同学们，在石林的语法讲课中，是说过绝对不会选含有you 的选项的，因为它造成模糊不清．这题的Ｅ为什么不对呢？

但我觉得C中间的one更加不好...请NN解答

看了答案选择B，更加觉得有问题；一上来是with Diamond.....后面第一感觉是什么

with diamond, B中的you显然不符合这样一个逻辑

那还是没解决啊.我说错了,我是选D的.D没有错啊.

E是错的啊,因为它有YOU啊

这道题之所以要选含“you” 的选项，是因为题干的后半部分 " ... the description may prove useful later if you have reason to believe the jeweler misled you." 本身就是针对“你”的情况展开的话题，所以当然要有 "you" 啦！