must may can't + have done +过去时间状语，表示对过去情况的推测，附加疑问句句常用，___时态，即借

must may can't + have done +过去时间状语，表示对过去情况的推测，附加疑问句句常用，___时态，即借用助动词___

A.，

B.，，

正确答案是A

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