Refer to the exhibit. A network engineer is implementing multicast Source-A to send a multicast stream for Receiver-A, and multicast Source-B to send a multicast stream for Receiver-B. Router RC forwa

`helper-address` is used for forwarding broadcast-based services like DHCP, not for controlling multicast PIM behavior or preventing multicast flooding.

`ip pim neighbor-filter` is used to control which PIM neighbors are formed, which is a security feature, but `ip pim passive` is a more direct way to prevent all PIM operations on an interface to stop unwanted flooding.

While PIM-SSM can help by requiring explicit (S,G) joins, `ip pim passive` directly addresses the 'flooding' issue by stopping PIM protocol activity on an interface that should not be routing multicast.

Enabling `ip pim passive` on an interface causes the router to stop sending and receiving PIM Hello messages on that interface, effectively disabling PIM neighbor adjacencies. This prevents the router from actively participating in PIM routing and stops it from receiving or forwarding unwanted multicast traffic on that segment, thus preventing flooding from Source-A to RB.