单选题 It ______ Sam who called and didn't leave a message on the answering machine. He said he wanted to get together with us this weekend.
A. might have been B. should have been
C. ought to be D. ought to have been

【正确答案】 A
【答案解析】[考点] 情态动词表推测
[解析] 可能是山姆打的电话，他没在答录机上留言。他说这周末他想和我们待一起。根据句意可知，本句是对过去发生事情的不太肯定的推测，所以A项符合题意。