When upgrading a VMware vSAN cluster to version 6.5, which two tasks must be completed to comply with upgrade requirements and VMware-recommended best practices? (Choose two.)

When upgrading a VMware vSAN cluster to version 6.5, which two tasks must be completed to comply with upgrade requirements and VMware-recommended best practices? (Choose two.)
A . Use RVC to upgrade the hosts.
B . Use the latest available ESXi version.
C . Back up all VMs.
D . Use only the “Full data migration” maintenance mode option.

Answer: B,C