You have connected a spanning-tree-enabled device to your spanning-tree-enabled switch, but the switch port does not forward traffic, even after you remove the device. Which command do you use to re-enable forwarding?

The correct choice in this scenario is to use the command that addresses issues with Bridge Protocol Data Units (BPDUs) related to spanning tree. When a switch port connected to a spanning-tree-enabled device does not forward traffic after the device is removed, it's likely that the port remains in a blocking state due to BPDU-related errors.

Using the command focused on BPDU errors allows the switch to clear any issues or inconsistencies that have occurred as a result of the spanning tree process, which ultimately enables the port to return to a forwarding state. This is particularly important because BPDUs are crucial for the operation of the spanning-tree protocol, as they help in the prevention of loops by ensuring that only designated ports are allowed to forward traffic.

In contrast, other commands may not specifically address the root cause. Commands that adjust interface status or handle port errors might not be sufficient if the underlying issue is specifically related to the spanning tree protocol's handling of BPDUs.

By specifically targeting BPDU errors, the correct command effectively resolves the state of the port, allowing it to start forwarding traffic again.