What class of IP addresses is used for multicast addressing?

• A. Class C
• B. Class B
• C. Class A
• D. Class D addresses 224.0.0.0 - 239.0.0.0

Answer: (D)

Multicast uses a dedicated address space in IPv4 that is allocated for delivering a single packet to multiple receivers. This is done with Class D addresses, which span from 224.0.0.0 to 239.255.255.255. When a host subscribes to a multicast group (via IGMP in IPv4 or MLD in IPv6), routers replicate and forward traffic only to networks where members of that group exist. This one-to-many delivery is what distinguishes multicast from unicast addressing.

The other address classes are used for one-to-one communication or for different scope purposes and aren’t designed for simultaneous delivery to multiple hosts, so they don’t fit the multicast use case.