The way people act in private is often different from ____ they act in public.

问题描述:

The way people act in private is often different from ____ they act in public.
A how B when C which D that
为什么 选A不选D?

how they act in public 他们在公共场合的行为方式,这里how是修饰act这个动词的,作状语,因此其他答案不合理