how many hosts must contribute storage in a non-stretch…

Assuming a mirrored (RAID-1) object configuration, how many hosts must contribute storage in a non-stretched
VMware vSAN cluster to satisfy the “Number of failures to tolerate” policy option?
“n” is the desired “Number of failures to tolerate” value for all options.

A.
2n+2

B.
2n

C.
2n+1

D.
3n