Which command allows IBGP to scale within an AS?

A.
neighbor {ip-address} update-source loopback0

B.
neighbor {ip-address} route-reflector-client

C.
neighbor {ip-address} ebgp-multihop 2

D.
neighbor {ip-address} next-hop-self

E.
neighbor {ip-address} remote-as {confederation-id}

F.
no sync