. Mary be in London because I saw her in town just now.A. mustn’tB. isn’t able toC. needn

问题补充：

. Mary be in London because I saw her in town just now.

A. mustn’t

B. isn’t able to

C. needn’t

D. can’t

答案：

A. mustn’t

B. isn’t able to

C. needn’t

(答案→)D. can’t

解析：考查情态动词。Can’t不可能，句意：玛丽不可能在伦敦，因为我刚刚在商业区看到她了。