请看看是选A还是CIf the traffic lights aren't green,you () go across the street A.must B.have to C.mustn't D.needn't

请看看是选A还是CIf the traffic lights aren't green,you () go across the street A.must B.have to C.mustn't D.needn't
请看看是选A还是C
If the traffic lights aren't green,you () go across the street A.must B.have to C.mustn't D.needn't

请看看是选A还是CIf the traffic lights aren't green,you () go across the street A.must B.have to C.mustn't D.needn't
C 不能（ 绿灯人才能走）

这道题选C

C 表示不得，不能