--- I’m sure Andrew will win the first prize in the final.
--- I think so. He for months.
A. is preparing
B. was preparing
C. has been preparing
D. had been preparing
网友回答
A. is preparing
B. was preparing
(答案→)C. has been preparing
D. had been preparing
解析：考查时态。根据语境及时间状语for months可知，用现在完成进行时，选C。