In a PIM-SM environment, which mechanism determines the traffic that a receiver receives?
A. The receiver explicitly requests its desired traffic from the RP on the shared tree.
B. The receiver explicitly requests traffic from a single source, which responds by forwarding all traffic.
C. The RP on the shared tree floods traffic out of all PIM configured interfaces.
D. The receiver explicitly requests traffic from each desired source, which responds by sending all traffic.
