单选题 ______ , he couldn't solve the problem at that moment.
A) He was clever C) As clever he was
B) As he was clever D) Clever as he was

【正确答案】 D
【答案解析】本题考点是从句。As引导的让步状语从句中，形容词放在句首要倒装。本句大意：他虽然聪明，可那时也不能解决这个问题。