Which of the following is an IPv4 multicast address?

An IPv4 multicast address is identified within a specific range of addresses set aside for multicast use. The valid range for IPv4 multicast addresses is from 224.0.0.0 to 239.255.255.255. The address 224.0.0.1 falls within this range and is specifically designated as a multicast address used by all systems on a local network for various services, such as routing protocols.

The other choices represent different types of IP addresses. The address 192.168.1.1 is a private IP address typically used in local networks. Likewise, 10.0.0.1 and 172.16.0.1 are also private IP addresses, utilized within internal networks and not meant for multicast transmissions. Thus, the only option that qualifies as an IPv4 multicast address is 224.0.0.1.