Which VTP mode allows a switch to create, modify, and delete VLANs for the entire domain?

The server mode in VLAN Trunking Protocol (VTP) is specifically designed to allow a switch to create, modify, and delete VLANs for the entire VTP domain. When a switch operates in server mode, it can propagate these changes to other switches in the same domain, ensuring that all connected devices are aware of the VLAN configurations.

In this mode, the switch maintains a database of VLAN information and can communicate updates to client switches within the domain. This makes server mode crucial for managing VLANs efficiently in a network, especially in larger environments where numerous switches are interconnected.

Other modes, such as client mode, do not allow VLAN creation or modifications. Instead, client mode switches can only receive updates from VTP servers. Transparent mode allows switches to pass VTP messages but does not update their VLAN database based on received messages, and it can create and delete VLANs locally without affecting the VTP domain. The off mode disables VTP on the switch altogether, meaning it neither sends nor receives VTP updates. Therefore, server mode is the only one that meets the requirement of creating, modifying, and deleting VLANs for the entire domain effectively.