Which two of these are characteristics of multicast routing? (Choose two.)

A.
multicast routing uses RPF.

B.
multicast routing is connectionless

C.
In multicast routing, the source of a packet is known

D.
When network topologies change, multicast distribution trees are not rebuilt, but use the original path

E.
Multicast routing is much like unicast routing, with the only difference being that it has a a group of receivers rather than just one destination

Explanation:
In multicast, the router forwards the packet away from the source to make progress along the distribution tree and prevent routing loops. The router’s multicast
forwarding state runs more logically by organizing tables based on the reverse path, from the receiver back to the root of the distribution tree. This process is known
as reverse-path forwarding (RPF).
https://www.juniper.net/documentation/en_US/junos/topics/concept/multicast-reverse-path-forwarding.html