On a PIM-SM network, how does a router select the upstream interface?
A . Looks up the outbound interface that matches the mapping proxy in the unicast routing table.
B . Selects the interface that directly connects to multicast group members.
C . Looks up the outbound interface that matches the RP address in the unicast routing table.
D . Selects the interface that receives PIM Join messages.
E . Selects the interface that sends REM Hello messages.
Answer: C