Explanation
To avoid storage policy non-compliance, the vSAN maintenance mode option that should be used is Full data migration. This option evacuates all data from the host to other hosts in the cluster and maintains the current object compliance state. This means that the VM objects will have access to all their replicas and will be compliant with their assigned storage policies. The other options might result in storage policy non-compliance, as they do not guarantee full data redundancy or policy adherence. Ensure accessibility only migrates the components that are essential for running the VMs, but might not have access to all their replicas.
Partial maintenance mode is not a valid option for vSAN clusters. No data migration does not evacuate any data from the host and might result in VM unavailability or data loss. References: Working with Maintenance Mode; Place a Member of vSAN Cluster in Maintenance Mode