Which of the following is a characteristic of a network switch?

A network switch is fundamentally designed to operate at the Data Link layer of the OSI model, where it performs its primary function of switching and forwarding data. The correct answer highlights that a switch forwards data based on MAC (Media Access Control) addresses. Each device connected to a switch is identified by its unique MAC address, which allows the switch to intelligently direct data frames to the correct destination device on the local network. This process enhances network efficiency by reducing unnecessary traffic and collisions.

The other options present characteristics that do not accurately describe a network switch. For instance, operating at the Network layer pertains more to routers, which manage data packets based on IP addresses rather than MAC addresses. Switches do not require IP addresses to function, as they operate primarily at the Data Link layer and deal with MAC addresses for local area network traffic. Additionally, while switches can connect multiple devices, they are typically used for connecting devices over relatively short distances within a local area network, unlike devices that are designed explicitly to connect networks over long distances, such as routers or wide area network (WAN) technologies.