you're the only person ( ) I've ever met ( )could do it

问题描述:

you're the only person ( ) I've ever met ( )could do it
A who;/
B /;whom
C whom;/
D /;who
后一个空格是做主语的吗?
我在边上做了个笔记是,口语中who that都可以.
口语中who that都可以

选D.
You're the only person (whom) I've ever met who could do it.
你是我遇到过的人里面唯一能做这个的
第一个whom是可以省略的,作为宾语补足语
第二个who在从句里做主语,指代"the only person",不能省