You'd better do ___you are required.A.like B.which C.that D.说明原因.

问题描述:

You'd better do ___you are required.A.like B.which C.that D.说明原因.

D.
as是从属连词“像...一样”,引导了方式状语从句,其他几个词都没有这样的词义.