As a network administrator， can you tell me what the root guard feature provides in a bridgednetwork？（）

• A、It ensures that BPDUs sent by the root bridge are forwarded in a timely manner
• B、It enforces the root bridge placement in the network
• C、It ensures that all ports receiving BPDUs from the root bridge are in the forwarding state.
• D、It ensures that the bridge is elected as root bridge in the network.