题目内容：

To prove the new theory,the scientist needs to find some grounds _＿his argument.
A which to be based on
B on which to base
C which to base on
D to which to base on

优质解答

A 以什么什么为基础 一定是用被动语态 那些词的位置颠倒了一下 故意迷惑人的