I think it's_____useful advice,so I will always remember it

问题描述:

I think it's_____useful advice,so I will always remember it
A.a
B.an
C.the
D.\

选A.a 不定冠词,useful的音标第一位不是元音,a e i o u,所以不用an,advice可数.可以说a piece of advice