What is the BGP synchronization rule?

A.
BGP should not advertise a route until that route has been learned via an IGP.

B.
Routing information received through an EBGP session is not forwarding to another EBGP
neighbor, only to IBGP neighbors.

C.
BGP neighbor peering are established and synchronized using TCP.

D.
BGP should not advertise a route when that route has been learned via an IGP

E.
Routing information received through an IBGP session is not forwarding to another IBGP
neighbor, only to EBGP neighbors.