A vSphere administrator is unable to power on a VM in a vSphere HA-enabled cluster. Which vSphere HA feature could cause this?

Datastore Heartbeats not being received affects how HA classifies a host as isolated vs. failed, but does not directly prevent individual VM power-on operations once a host state is determined.

Admission Control being enabled restricts powering on additional VMs only when the cluster lacks sufficient reserved failover capacity - it does not selectively block a specific VM from powering on based on HA restart configuration.

VM Restart Priority controls whether vSphere HA will attempt to restart a specific virtual machine after a host failure event. When set to Disabled, HA explicitly excludes the VM from all restart operations, meaning the VM will not be powered on by HA after the host it resides on fails, leaving the administrator unable to bring it back up through the normal HA-managed power-on path without first changing the priority setting.

VM Monitoring being disabled suppresses automatic restarts triggered by in-guest heartbeat loss on an otherwise healthy host, but does not prevent HA from restarting VMs in response to a host failure event.