—I saw Annie in the supermarket yesterday.
—You her;she is still studying abroad.
A. mustn’t see
B. can’t have seen
C. mustn’t have seen
D. couldn’t see
网友回答
A. mustn’t see
(答案→)B. can’t have seen
C. mustn’t have seen
D. couldn’t see
解析：can’t 情态动词表推测，意为“不可能”。