i am surprised that Jane,who has been among the best in my class,___have failed in the exam.

题目

i am surprised that Jane,who has been among the best in my class,___have failed in the exam.
a.must
b.should
c.would
d.could
但这样我感觉中文意思不大对哎~

答案

should have done意思是本来该如何如何,结果没有如此.
你很惊讶JANE考试失败了.因为她成绩很好.
说明本来应该很好的结果没考好.事情已经发生了.
所以选B SHOULD HAVE FAILED