A.It does not support all underlying unicast routing protocols like BGP
B.Receivers are registered with RP by their first hop router
C.From the RP， traffic flows down a source tree to each receiver.
D.It supports shared trees only， and assumes all hosts want the multicast traffic
E.Receivers are joined to the shared tree by their local designated router

A.After the route target replacement policy is applied to the target router， the BGP session need not be refreshed manually to put the policy into operation.
B.Route Target Rewrite allows the administration of the routing policy to stay local to the AS.
C.Route target replacement is always done by the ASBR.
D.Route target rewrites are supported for VRF export maps.
E.Route target replacement can be done on incoming and outgoing BGP updates.