My sister met him at the Grand Theatre yesterday afternoon, so he ________ your lecture.

My sister met him at the Grand Theatre yesterday afternoon, so he ________ your lecture.

A.couldn't have attended

B.needn't have attended

C.mustn't have attended

D.shouldn't have attended

答案及解析： A

解析：

couldn’t have done表达的是过去不可能做过某事，是一种否定推测。