A is correct because you need to configure BGP multihop to enable redundancy for the EBGP peering

between the two routers. BGP multihop is a feature that allows BGP peers to establish a session over

multiple hops, instead of requiring them to be directly connected1. By default, EBGP peers use a

time-to-live (TTL) value of 1 for their packets, which means that they can only reach adjacent

neighbors1. However, if you configure BGP multihop with a higher TTL value, you can allow EBGP

peers to communicate over multiple routers in between1. This can provide redundancy in case of a

link failure or a router failure between the EBGP peers.

B is correct because you need to configure loopback interface peering to enable redundancy for the

EBGP peering between the two routers. Loopback interface peering is a technique that uses

loopback interfaces as the source and destination addresses for BGP sessions, instead of physical

interfaces2. Loopback interfaces are virtual interfaces that are always up and reachable as long as the

router is operational2. By using loopback interface peering, you can avoid the dependency on a

single physical interface or link for the BGP session, and use multiple paths to reach the loopback

address of the peer2. This can provide redundancy and load balancing for the EBGP peering.

C is correct because you need to configure routes for the peer loopback interface IP addresses to

enable redundancy for the EBGP peering between the two routers. Routes for the peer loopback

interface IP addresses are necessary to ensure that the routers can reach each other’s loopback

addresses over multiple hops2. You can use static routes or dynamic routing protocols to advertise

and learn the routes for the peer loopback interface IP addresses2. Without these routes, the routers

will not be able to establish or maintain the BGP session using their loopback interfaces.