Which two verification steps will be helpful in troubleshooting this problem?

A junior network engineer has just configured a new IBGP peering between two Cisco
ASR9K PE routers in the network using the loopback interface of the router, but the IBGP
neighborship is not able to be established. Which two verification steps will be helpful in
troubleshooting this problem? (Choose two.)

A.
Verify that the network command under router BGP is configured correct on each router
for announcing the router’s loopback interface in BGP

B.
Verify that the ibgp-multihop command under the BGP neighbor is configured correctly
on each router

C.
Verify that the loopback interfaces are reachable over the IGP

D.
Verify that the update-source loopback command under the BGP neighbor is configured
correctly on each router

E.
Verify that the ttl-security command under the BGP neighbor is configured correctly on
each router to enable the router to send the BGP packets using a proper TTL value

F.
Verify that the UDP port 179 traffic is not being blocked by an ACL or firewall between
the two IBGP peers