答案是D。这里考的是语言习惯:Must he leave here?Yes, he must.No, he needn't.
D needn't 没必要can't 不能mustn't不准C 如果是 doesn't need to,那么也是正确的
用Must开头的一般问句,其否定回答用needn't,所以选择D
D.needn't
D