At that time the blacks reached a stage they had almost no rights at all.A. whenB. whichC.

问题补充：

At that time the blacks reached a stage they had almost no rights at all.

A. when

B. which

C. where

D. what

答案：

A. when

B. which

(答案→)C. where

D. what

解析：定语从句考查题。先行词a stage关系词where在从句中做状语。句意：在那时黑人处于一种根本没权利的地步。