Which statement about MAC addresses is correct?

Which statement about MAC addresses is correct?

• A. MAC address is used to locate a device on the internet.
• B. IP address is used to identify a device's hardware.
• C. DNS address identifies the device.
• D. MAC address identifies the device connected to the internet.

Answer: (D)

MAC addresses are the unique hardware identifiers assigned to a device’s network interface. They operate on the local link and are used to deliver frames to the correct physical device on a local network. They aren’t used to locate devices across the internet; that job belongs to IP addresses, which route packets between networks. DNS, meanwhile, translates domain names to IP addresses, not to hardware identifiers. So the statement that a MAC address identifies the device connected to the internet best matches what a MAC address does in practice: it identifies the device’s hardware on the local connection, which is the portion of the path that actually reaches the wider internet. The other statements attribute correct roles to IP or DNS in ways that don’t reflect how MAC addresses function. ARP is the mechanism that helps bind an IP address to a MAC on the local network, enabling proper delivery at the data-link layer.

MAC addresses are the unique hardware identifiers assigned to a device’s network interface. They operate on the local link and are used to deliver frames to the correct physical device on a local network. They aren’t used to locate devices across the internet; that job belongs to IP addresses, which route packets between networks. DNS, meanwhile, translates domain names to IP addresses, not to hardware identifiers. So the statement that a MAC address identifies the device connected to the internet best matches what a MAC address does in practice: it identifies the device’s hardware on the local connection, which is the portion of the path that actually reaches the wider internet. The other statements attribute correct roles to IP or DNS in ways that don’t reflect how MAC addresses function. ARP is the mechanism that helps bind an IP address to a MAC on the local network, enabling proper delivery at the data-link layer.