, they couldn’t solve the mystery.
A. Tried hard as they
B. Hard as they tried
C. Tried as they hard
D. They tried hard as
网友回答
A. Tried hard as they
(答案→)B. Hard as they tried
C. Tried as they hard
D. They tried hard as
解析：考查as引导的让步状语从句的倒装。as引导让步状语从句要提前表语、状语或动词原形，此处有状语，先提前状语成分，其结构：形容词/名词/副词/动词原形+as+主语+其他-----。