all passengers —— to show thier tickets next timeA.require B.is required C.are required D.are to require

all passengers —— to show thier tickets next time
A.require
B.is required
C.are required
D.are to require

选C.
句意：
下一次所有的乘客都被要求出示票据.
按照句意需要,应该是【被动语态】,排除A,D;
主语【all passengers 】是复数,排除B.