----Excuse me . Have you got an eraser ?--Sorry I haven’t . Why you ask Mary ? A. doB

问题补充：

----Excuse me . Have you got an eraser ?

----Sorry , I haven’t . Why you ask Mary ?

A. do

B. not

C. don’t

D. did

答案：

A. do

B. not

(答案→)C. don’t

D. did

解析：根据后面有个you ，不能用why not do sth ，故选C