Each media access control (MAC) address has a network interface card (NIC).

• A. Not specified
• B. True
• C. False
• D. Both

Answer: (C)

A MAC address serves as a hardware identifier at the data link layer for a network interface. In practice, each NIC has its own MAC address, but not every MAC address corresponds to a single NIC. Some MAC addresses are reserved for special purposes and are not bound to a particular device. For example, the broadcast address FF:FF:FF:FF:FF:FF is used to deliver frames to all devices on a local network, not to a single NIC. Multicast addresses (such as 01:00:5e:...) are used to reach a group of devices, not one specific NIC. Virtual NICs and software-defined networking can also have MAC addresses that belong to interfaces other than physical NICs. Because there exist MAC addresses that aren’t tied to a single NIC, the statement isn’t universally true.