What is the purpose of the IPv4 broadcast address?

• A. To reach all hosts within the subnet by sending a single frame to all devices in that subnet.
• B. To address a specific host with high priority.
• C. To identify the network's gateway.
• D. To locate the next-hop router.

Answer: (D)

The Internet Protocol version 4 broadcast address is used to reach every host on the local subnet with a single transmission. When a packet is sent to the subnet’s broadcast address, every device in that subnet receives and can respond, which is handy for tasks that need to be announced or discovered on the local link. The broadcast address is formed by setting all host bits to 1 within the subnet, such as 192.168.1.255 for a 192.168.1.0/24 network. This is why protocols like ARP (to map IP addresses to MAC addresses) and DHCP (initially) use broadcasts on the local network.

The other options describe targeting a single device or a router, which are unicast behaviors and not how a broadcast address operates.