Question

Gun control is a subject ________ Americans have argued for a long time.

A．of which 

B．with which

C．about which 

D．into which

Answer 1

答案：C解析：argue with sb.about/over sth.“就……与某人争论，争辩”；先行词a subject在定语从句中作介词的宾语，而且介词about前置，故选C项。