Refer to the exhibit. If the SP network is configuring RTBH filtering to protect hosts on the 152.68.19.0/24 network, which router should be configured as the black hole activating router?

Router F, without context, is unlikely to be the sole activating router if it's an internal or core device not handling ingress traffic and blackhole route injection.

Router C, presumably an internal or core router, is typically a blackhole router that receives the blackhole route, not the one activating or originating it.

Router D, similar to Router C, is likely a core or transit router that would receive and apply the blackhole route, rather than being the activating router.

In a typical SP network, the black hole activating router is often a Provider Edge (PE) router or an internal BGP speaker (like router L, assumed to be an edge router from the choices context) that is configured to receive a specific BGP community for an attacked prefix and then inject a route to Null0 for that prefix, effectively blackholing the traffic at the edge of the network.

Router A, without context, is unlikely to be the sole activating router if it's an internal or core device not handling ingress traffic and blackhole route injection.

Router K, without context, is unlikely to be the sole activating router if it's an internal or core device not handling ingress traffic and blackhole route injection.