Which command reveals whether a routing protocol is sending and receiving updates on an interface?

• A. show ip ospf interface
• B. show ip protocols
• C. show interfaces
• D. show running-config

Answer: (B)

The concept being tested is how to verify that a routing protocol is actively exchanging updates on the router. The show ip protocols command shows which IP routing protocols are running on the device and provides details about the networks being advertised and the update timers. This information confirms that the protocol is active and is set to send and receive updates, which is what you’re looking for when you want to know if updates are occurring on the interfaces participating in that protocol.

If you needed more granular, per-interface details for a specific protocol, you’d use a more focused command (for example, an OSPF-specific one to see Hello packets and neighbor adjacencies). The other options either show interface status or the router’s configuration, not the active routing updates.