You ____ stop when the traffic light turns red.A,had better B,must 为什么填A

You ____ stop when the traffic light turns red.A,had better B,must 为什么填A
You ____ stop when the traffic light turns red.A,had better B,must 为什么填A

You ____ stop when the traffic light turns red.A,had better B,must 为什么填A
had better译最好,有劝告或建议；而must译必须,无条件服从,交通规则是必须遵守.故选B