A、Britain. B、Germany. C、France. D、Denmark. B本题的问题关键词是not visit。对话中提到了英国、法国、丹麦、美国，表示这些都是去过的，那没有去过的就是德国，因此选B。

W: Mr. Smith, Dr. Miller will have to change your appointment to tomorrow. He is still waiting for a flight out of Washington.
M: Oh, well, thank you for calling. I’ll see him in his office then.
Q: Where is Dr. Miller now?

M: Where did you and your husband go on your vacation?
W: We spent three weeks in Britain, one week in France and another week in Denmark before we went to America.
Q: Which of the following countries did the woman and her husband not visit?