Which of the following comparisons does a switch make when deciding whether a new MAC address should be added to its MAC address table?

Which of the following comparisons does a switch make when deciding whether a new MAC address should be added to its MAC address table?

• It compares the unicast destination address to the bridging, or MAC address, table.
• It compares the unicast source address to the bridging, or MAC address, table.
• It compares the VLAN ID to the bridging, or MAC address, table.
• It compares the destination IP address’s ARP cache entry to the bridging, or MAC address, table.

Explanation: Switches need to learn the location of each MAC address used in the LAN relative to that local switch. When a switch receives a frame, the source MAC identifies the sender. The interface in which the frame arrives identifies the local switch interface closest to that node in the LAN topology.