. —How can I thank you? —Don’t mention it. Any other man in that case the same thing. A.

问题补充：

. —How can I thank you?

—Don’t mention it. Any other man in that case the same thing.

A. would have done

B. could have done

C. must have done

D. should have done

答案：

A. would have done

(答案→)B. could have done

C. must have done

D. should have done

解析：考查虚拟语气。句意：我该如何感谢你呢？——不要提了。任何其他人在那种情况下都会做相同的事情。“could+have+done”是虚拟语气，表示对过去事情的假设，意思是本来能够做某事而没有做。故选B。