--Did the reference give the information you needed?----Yes but it I had to read it e

问题补充：

----Did the reference give the information you needed?

----Yes, but it, I had to read it entirely.

A. to find

B. having found

C. finding

D. find

答案：

(答案→)A. to find

B. having found

C. finding

D. find

解析：句意：上文，这本参考书给了你你需要的信息没？下文，是的，但是要找到它，我不得不彻底地阅读。表示将来的动作，用不定式，选A。