The captain stood by the window, he could see the top of the tower.
A. where
B. from which
C. from where
D. which
网友回答
A. where
B. from which
(答案→)C. from where
D. which
解析：本题较难，是一个非限制性定语从句。答案A、B是等同的，where常等于：in/at/from---
+ which , 故两个答案都排除。from where = from by the window, 意思是：“从窗户旁边那个地方”。再如：
The boy was hidden behind the door, from where he could see what was going on in the room.