--What do you think made Celia so happy?
-- a prize in the recent petition.
A. As she won
B. Won
C. Winning
D. Because of winning
网友回答
A. As she won
B. Won
(答案→)C. Winning
D. Because of winning
解析：回答what要用名词或相当于名词的动名词。句意：什么事使得Celia如此高兴？在最近的比赛当中获奖让他高兴。