When a router has a route with a next hop of 'rjct' (reject), the intended action is to explicitly deny that traffic. This means that the router will discard the traffic and send an ICMP unreachable message back to the source of the traffic, informing it that the destination is unreachable. Therefore, the correct action is that the traffic will be discarded and an ICMP unreachable message will be sent to the source of the traffic.