Chian ___WTO in 2001.A.joined B.joined in C.took part in D.is in 选哪个,为什么?

Chian ___WTO in 2001.A.joined B.joined in C.took part in D.is in 选哪个,为什么?
Chian ___WTO in 2001.A.joined B.joined in C.took part in D.is in 选哪个,为什么?

Chian ___WTO in 2001.A.joined B.joined in C.took part in D.is in 选哪个,为什么?
A,join指加入某党派、某组织或某社会团体,以及参军等,还可表示参与某种活动.
还有貌似发错版块了吧!