Refer to the exhibit. OSPF is running as the IGP to provide reachability to all AS100 networks. R3 and R4 are the current ABRs at the boundary of OSPF Area0 and...

Refer to the exhibit. OSPF is running as the IGP to provide reachability to all AS100 networks. R3 and R4 are the current ABRs at the boundary of OSPF Area0 and Area1. Now BGP must be deployed within AS100 because it will be receiving Internet routes from its eBGP peers (the service provider) connected to R1 andR2. What is an optimal solution for this deployment to configure BGP relationships and redistribute BGP learned routes into OSPF?

A. R5 should be configured as a route reflector for R1, R2, R3 and R4. BGP routes must be redistributed at R1 and R2 into OSPF. B. Confederation should be set up with R1, R5, and R3 in one sub AS, with R2 and R4 in another, and redistribution at R1 and R2. C. R1, R2, R3 and R4 must be set up with a neighbor relationship with R5 only. R5 must not be a route reflector. D. A full mesh should be deployed between all the routers with mutual redistribution to take place at R1 and R2.