根据以下的配置,请判断当主接口serial0出故障后,哪一个备份接口最先被启用?()[Quidway-Serial0]standby interface serial 1 30[Quidway-Serial0]standby interface serial 2 40[Quidway-Serial0]standby logic-channel 3 50[Quidway-Serial0]standby logic-channel 2 35
A、serial 1
B、serial 2
C、logic-channel 2
D、logic-channel 3