问题
选择题
Gun control is the subject ________ Americans have argued for a long time.
A．which
B．with which
C．about which
D．of which
答案
答案：C
考查定语从句。argue about 争论什么，先行词为the subject，故用about which，句意：控制枪支是一个美国人争论了很长一段时间的话题。