On which router would a default route be statically configured in a single area OSPF environment?

In a single area OSPF environment, the router that is typically configured with a default route is the one that serves as the gateway to external networks, which is often connected to the internet or a larger network. In this context, R0-A is likely designated to handle outgoing traffic, making it the ideal candidate for implementing a default route.

A default route in OSPF allows the router to forward packets destined for unknown networks to a predefined next-hop address. This default route can facilitate the communication between the internal OSPF network and external destinations, ensuring that traffic not covered by specific OSPF routes is still handled appropriately.

By placing the static default route on R0-A, the OSPF network can maintain efficient routing and help manage traffic leaving the network without requiring every internal router to know how to reach external networks. This setup generally optimizes routing simplistically while ensuring all traffic can reach its intended destinations outside the OSPF area.