A packet is sent to a destination address. That single packet is replicated by a few routers based on the routers’ knowledge of hosts that had earlier registered to receive packets sent to that destination address. The routers do not forward copies of the packet onto subnets where no hosts have registered, and do forward copies of the packet onto subnets where at least one host has registered to receive those packets. Which of the following IP address types was used as the destination IP address? a. A unicast address
b. A network broadcast address
c. A subnet broadcast address
d. A multicast address