I think we'll carry it out if the experiment ___before ten A.will finish.B.is finished.C.has finished

I think we'll carry it out if the experiment ___before ten A.will finish.B.is finished.C.has finished
I think we'll carry it out if the experiment ___before ten A.will finish.B.is finished.C.has finished

I think we'll carry it out if the experiment ___before ten A.will finish.B.is finished.C.has finished
应选B.两点：1,应用被动语态 2,在if引起的状语从句中,即使表示将来也不能用将来时,用一般现在时代替.希望我的回答能使你满意.