On a switch, which configuration best describes the tagging of frames for multiple VLANs?

• A. Trunk ports carry a single VLAN
• B. Access port carries a single VLAN
• C. All ports tag frames by default
• D. Trunk ports carry multiple VLANs with 802.1Q tagging

Answer: (D)

Tagging frames for multiple VLANs relies on trunk links. A trunk port is designed to carry traffic for several VLANs between network devices, and it uses 802.1Q tagging to label each frame with its VLAN identifier. Access ports, on the other hand, connect devices to a single VLAN and send frames untagged. While a native VLAN on a trunk may carry untagged frames, the essential point is that trunks carry multiple VLANs using 802.1Q tags. That’s why describing trunk ports as carrying multiple VLANs with 802.1Q tagging is the correct concept.