Thanks your help.A. toB. ofC. forD. at

问题补充：

Thanks your help.

A. to

B. of

C. for

D. at

答案：

A. to

B. of

(答案→)C. for

D. at

解析：句意：谢谢你的帮助。Thanks for…谢谢……介词用for，故选C。