The correct answer is A. MAC address.
A MAC address, or Media Access Control address, is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are 48 bits long and are usually written in hexadecimal format, for example: 00:11:22:33:44:55.
IP addresses, on the other hand, are 32-bit or 128-bit numbers that identify devices on a network. IP addresses are usually written in decimal format, for example: 192.168.1.1.
Network interface cards (NICs) are devices that allow computers to connect to a network. NICs have a MAC address that is assigned to them by the manufacturer.
Address Resolution Protocol (ARP) is a protocol that maps IP addresses to MAC addresses. ARP is used when a computer needs to send a packet to another computer on the same network.
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