问个语法题

observer

Anarchism is a term describing a cluster of doctrines and attitudes ______ principal uniting feature is the brief that government is both harmful and unnecessary.

A. and
B. whose
C. since
D. for

答案是B，谁能帮我分析一下？谢谢

apply1

后面的应是定于从句，因为主句完整。只有whose可以引导而且意思也对

observer

谢谢！！