—Kate do you know it is from here to the post office?—About twenty minutes’ walk.A. how l

问题补充：

—Kate, do you know it is from here to the post office?

—About twenty minutes’ walk.

A. how long

B. how often

C. how far

D. how soon

答案：

A. how long

B. how often

(答案→)C. how far

D. how soon

解析：About twenty minutes’ walk意思是20分钟的路程，表示的是距离故用how far来提问。