During a vCenter Server upgrade, an ESXi 6.x host in a High Availability (HA) cluster fails.
Which statement is true?

A.
HA will fail the virtual machines over to an available host during the vCenter Server upgrade process.

B.
HA is unavailable during the vCenter Server upgrade process.

C.
HA will fail the virtual machines over to an available host after the vCenter Server upgrade completes.

D.
HA will successfully vMotion the virtual machines during the host failure.