A、BPDU port-guard can be enabled globally， whereas BPDU filtering must be enabled on a per-interface basis.

B、When globally enabled， BPDU port-guard and BPDU filtering apply only to PortFast enabled ports.

C、When globally enabled， BPDU port-guard and BPDU filtering apply only to trunking-enabled ports.

D、When a BPDU is received on a BPDU port-guard enabled port， the interface goes into the err-disabled state.

E、When a BPDU is received on a BPDU filtering enabled port， the interface goes into the err-disabled state.

F、When a BPDU is received on a BPDU filtering enabled port， the interface goes into the STP blocking state.