Which networking device operates at Layer 2 of the OSI model and forwards data based on MAC addresses?

Correct option is A

A switch is a networking device that operates at Layer 2 of the OSI model, also known as the Data Link Layer. It forwards data packets between devices on the same network by using MAC addresses to determine the destination.
(b) Hub: This is incorrect because a hub is a basic networking device that broadcasts data to all devices in a network segment, without considering MAC addresses.
(c) Firewall: This is incorrect because a firewall operates at higher layers (usually Layer 3 or above) and is used for security purposes, not for forwarding data based on MAC addresses.
(d) Router: This is incorrect because a router operates at Layer 3 of the OSI model and forwards data based on IP addresses, not MAC addresses.