单选题

Today's college students have ambiguous feelings about the role they should play in the world.
A. wonderful B. unusual C. ambitious D. doubtful
【正确答案】 D
【答案解析】ambiguous不明确的。doubtful不确定的，不肯定的。wonderful奇妙的，极好的。unusual不寻常的。ambitious有雄心的。