They stood at the window, ________ they could see ________ was happening in the street.

They stood at the window, ________ they could see ________ was happening in the street.

A.where; all

B.which; all

C.from where; what

D.from which; that

答案及解析： C

解析：

导解：where引导地点状语从句；what是宾语从句的主语．