请选择ABCD4@0a.y1^9\5g When the traffic light turns red, we _______ cross the road./V9n(R)E'K-U3`
A. must/V9n(R)E'K-U3`
B. mustn’t/V9n(R)E'K-U3`
C. can/V9n(R)E'K-U3`
D. not must/V9n(R)E'K-U3`