问题补充：
— These books are not yours, are they?
—. I am looking for mine.
A. Yes, they are
B. No, they aren’t
C. Yes, it is
D. No, it isn’t
答案：
A. Yes, they are
(答案→)B. No, they aren’t
C. Yes, it is
D. No, it isn’t
解析：根据后文I am looking for mine说明上文说的不是事实，所以用否定回答，故选B
