We’d better when he is thinking, as he prefers to solve problems on his own.
A. wake him up
B. set him aside
C. leave him alone
D. ring him up
网友回答
A. wake him up
B. set him aside
(答案→)C. leave him alone
D. ring him up
解析：句意：当他思考的时候我们最好别打扰他，因为他喜欢独自处理问题。A. wake him up把他叫醒；B. set him aside 把他放在一边； C. leave him alone别打扰他； D. ring him up给他打电话。根据句意故选C。