—Guess what! I have got A for my term paper.
—Great! You read widely and put a lot of work into it.
A. must
B. should
C. must have
D. should have
网友回答
A. must
B. should
(答案→)C. must have
D. should have
解析：既然已经通过考试，自然是以前阅读广泛﹑用心学习了，故在C﹑D中进一步选择，D项表示本应当，因不附题意而被舍去。