(我选了C,为啥不行呢?)

问题描述:

(我选了C,为啥不行呢?)
Not until all the fish died in the river,---------how serious the pollution was.
A did the people realize
B the people realize
C the people did realize
D didn't the people realize

首先理解一下这句话,意思是:
直到河水中鱼死完了,人们才能意识到污染有多严重.
这里是固定句型,not nutil在前面的话,后一句中do动词需要提前,所以应该选A.