Choose the closest paraphrased version after the following sentence or the italicized part.
What impelled the boy to take so much trouble to spare the feelings of a stranger（ ）
A.正确答案DWhy did the boy trouble himself to save stranger
B.Why did the boy try so hard to make friends with a stranger
C.Why did the boy try his best to build up the confidence of a stranger
D.Why did the boy make such great efforts in order not to embarrass a stranger
