—Excuse me sir. Would you do me a favor?—Of course. What is it?—I if you could tell me h

问题补充：

—Excuse me, sir. Would you do me a favor?

—Of course. What is it?

—I if you could tell me how to fill out this form.

A. had wondered

B. was wondering

C. would wonder

D. did wonder

答案：

A. had wondered

(答案→)B. was wondering

C. would wonder

D. did wonder

解析：表示刚才想叫你帮忙，就是“我在想你可不可以帮我填这个表格”，所以用过去进行时。