How can trunk lines contact multiple VLANs?

The ability of trunk lines to contact multiple VLANs is effectively accomplished through the process of "tagging" packets. In networking, particularly within Ethernet networks, VLANs (Virtual Local Area Networks) are used to separate broadcast domains for better management and security. Trunk lines facilitate the transmission of data across multiple VLANs by appending a header to each packet which identifies the VLAN it belongs to. This process is known as VLAN tagging.

When a trunk port receives a frame, it inspects the VLAN tag, and based on that tag, it knows how to handle and forward the packet appropriately across the network. This allows a single physical connection to carry traffic from different VLANs, thus optimizing the use of network resources and reducing the need for multiple physical connections.

The other options, while related to VLAN management, do not provide a mechanism for trunk lines to effectively communicate with multiple VLANs in the same way that tagging does. For instance, creating separate switches for each VLAN would not utilize trunking, and static configurations typically refer to setting up VLANs or port settings without the dynamic tagging necessary for trunking. Disabling untagged VLANs alters the behavior of the connections but does not facilitate multi-VLAN communication through a trunk link. Therefore,