Our city has changed a lot,and it is quite different ____it used to be.A of what B from what

问题描述:

Our city has changed a lot,and it is quite different ____it used to be.A of what B from what
C from which D as请问选什么?为什么?

选B.what it used to be作了介词from的宾语从句.因为是be different from,而不是be different of请问为什么不选C from which