Preventing Routing Protocols from Sending Hello Messages on an Interface

B

The correct answer is B. passive-interface.

Passive-interface is a feature that can be enabled on an interface in a routing protocol, such as OSPF, EIGRP, or RIP. When this feature is enabled, the routing protocol will not send hello messages out of that interface, which effectively stops the interface from participating in the routing protocol.

The purpose of the passive-interface feature is to prevent unnecessary network traffic and reduce the risk of routing loops. By not sending hello messages on a specific interface, the router will not advertise its routing information to other routers connected to that interface. This means that the router will not learn about any new routes that may be available on that interface, but it also means that the router will not accidentally create a routing loop by advertising its own routes back to itself.

Virtual links are used in OSPF to connect two non-contiguous areas through a transit area. This feature does not prevent hello messages from being sent on an interface.

Directed neighbors is a feature in EIGRP that allows a router to send hello messages to a specific neighbor instead of broadcasting them to all neighbors on an interface. This feature does not prevent hello messages from being sent on an interface.

OSPF areas are used to divide a large OSPF network into smaller, more manageable sections. This feature does not prevent hello messages from being sent on an interface.

Therefore, the correct answer to the question is B. passive-interface.