I was about to go to school _____ my mother asked me to buy some eggs.

问题描述:

I was about to go to school _____ my mother asked me to buy some eggs.
A.while B.when C.as D.as soon as

B.when
表示“突然发生什么事情”
我正准备去学校时我妈妈让我去买几个鸡蛋.