问题
选择题
In western culture,21 was the age________ young people traditionally received a key to their parents’ door, as a symbol of entering adulthood.
A．in which
B．on which
C．at which
D．to which
答案
答案：C
本题考查定语从句。先行词age与介词at搭配。句意：在西方传统文化中，年轻人到了21岁便可获得进入父母房间的钥匙，象征着他们开始进入成人世界。