Which two statements best describe spanning-tree BPDU processing for a blocking port？（）

• A、BPDUs that enter a blocking port are discarded.
• B、BPDUs that enter a blocking port are processed.
• C、Loopguard puts an interface into a loop-inconsistent state when BPDUs stop being received on a blocking port.
• D、BPDUs are only processed on forwarding ports.