What command is used to configure a RIP-enabled router to advertise its default route to its RIP neighbors?

The command used to configure a RIP-enabled router to advertise its default route to its RIP neighbors is "default-information originate." This command is crucial in scenarios where you want to inform neighboring routers of a default route that can be used when no specific route is available in the routing table.

When a router is configured with this command in its RIP configuration mode, it will advertise the default route (typically 0.0.0.0) to all RIP neighbors. This is particularly useful in larger networks where you want to facilitate easier routing and ensure that other routers can send traffic to destinations not explicitly known in their routing tables. It essentially tells the router to include the default route in its RIP updates.

The other options do not correspond to valid commands in the context of configuring RIP. They either resemble common routing terminologies or misinterpret the syntax used in Cisco IOS commands. Thus, "default-information originate" is the only correct and applicable answer for configuring default route advertisement in a RIP-enabled environment.