Which vSphere feature provides continuous availability, allowing users to protect any virtual machine from a host failure with no loss of data or connectivity?

The vSphere feature that offers continuous availability and protects virtual machines from host failures without any loss of data or connectivity is indeed vSphere Fault Tolerance. This feature creates a live shadow instance of a virtual machine that runs in lockstep with the primary virtual machine. In the event of a host failure, the shadow instance can immediately take over without any interruption to the services running on the virtual machine, ensuring that there is no data loss or loss of connectivity for end users.

This capability is particularly important for mission-critical applications where uptime is essential. It leverages technologies like VMware's vLockstep, allowing both the primary and the secondary VM to execute their operations simultaneously.

Other options provide different functionalities: vMotion primarily focuses on the live migration of virtual machines between physical servers with minimal downtime, but it does not inherently offer protection against host failure. Enhanced vMotion Compatibility allows for smoother migration between hosts with different CPU compatibility but does not focus on availability in the case of host failure. vSphere HA (High Availability) does protect against host failures by restarting VMs on other available hosts, but there can be a brief period of downtime during the failover, unlike Fault Tolerance, which ensures no downtime at all.