I have dropped __"s"in the word "necessary".Oh,__letter"s"is doubled.

问题描述:

I have dropped __"s"in the word "necessary".Oh,__letter"s"is doubled.
A:a;a B:a;the C:an;the D:the;the

C."s"读做【es】读音以元音开头.
不明白的再问哟,请及时采纳,多谢!