—Sorry, Professor Smith. I didn’t finish the assignment yesterday.

题目：—Sorry, Professor Smith. I didn’t finish the assignment yesterday.

—Oh, you_______ have done it as yesterday was the deadline.
A. must
B. mustn’t
C. should
D. shouldn’t

喵查答案：C

此处表示和过去事实相反的情况，应该用should + have + 过去分词。本来应该做，而未做