In a stub network, what role does the default route serve?

• A. It is used to advertise all paths to external networks.
• B. It reduces routing state by providing a single exit path to non-local destinations.
• C. It increases the routing table with many entries.
• D. It disables dynamic routing protocols.

Answer: (B)

In a stub network, there is a single exit point to reach destinations outside the local area. The default route acts as a catch-all path (0.0.0.0/0) that forwards any traffic for unknown destinations to one next hop. This greatly reduces routing state because you don’t need separate routes for every external network—just one exit point. The other ideas describe advertising all external paths, increasing the routing table, or disabling protocols, none of which characterize how a default route functions in a stub network.