After graduation from high school we will reach a point _________ we have to decide which university to attend.  

A．that

B．what

C．which

D．where

无效合同的处理，可根据不同情况，采用（）等方法来处理。

A.收归国库所有

B.返还部分财产

C.返还财产

D.赔偿损失

E.恢复原状