Which three protocols should be explicitly managed by using Control Plane Policing on an Internet borderrouter？（）

A.When congestion is present，the priority command doesn’t allow exceeding the allocated rate
B.When congestion isn’t present，the priority command doesn’t allow exceeding the allocated rate
C.When congestion is present，the priority command allows exceeding the allocated rate
D.When congestion isn’t present，the priority command allows exceeding the allocated rate

A.qos-group
B.DSCP
C.LFI
D.NBAR