A network is designed to use OSPF to reach eBGP peers. For eBGP peers to stay stable in case of a link failure, what condition should be avoided?

Advertising eBGP peer addresses into a normal OSPF area is the recommended practice, as it provides IGP-based stability independent of the BGP session state.

Using an ACL to block BGP in one direction is a policy or security action unrelated to the routing stability problem caused by recursive lookup failures.

Disabling BGP synchronization is a standard modern practice that prevents BGP from waiting for IGP convergence before advertising routes, and does not affect peer reachability stability.

If the IP addresses used in eBGP peer statements are only reachable via eBGP-learned routes, a session failure causes those routes to be withdrawn. This creates a recursive lookup failure where the router cannot re-establish the session because the route to the peer no longer exists, making recovery impossible. Peer addresses should always be reachable via a stable IGP such as OSPF.