Which option is true regarding the synchronization rule ?()
A、A. Do not use or internally advertise a route until the route is lear ned from a source other than BGP.
B、B. Do not use or advertise a route until the route is learned from a BGP peer.
C、C. Do not use or advertise routes marked PARTIAL.
D、D. Wait until a CONFIRM message is received before using routes from BGP neighbors.