What is correct about the BGP synchronization command? (Choose two.)
A.
Synchronization must be enabled when implementing a multi-homed BGP connection to multiple ISPs.
B.
If it is turned ON, a prefix learned from IBGP neighbor is valid only if a non-bgp (IGP) route exists for that prefix.
C.
Synchronization is necessary when peering with an EBGP neighbor.
D.
Synchronization improves BGP routing convergence.
E.
Synchronization can be turned off if all the transit routers in an Autonomous system running full mesh IBGP.