Which of the Following Describes the N+ Model for VM

Multiple Choice

Which of the following describes the N+ model for VM redundancy?

A) There are N active VMs and one standby VM that takes over if the active VM fails.
B) Thera are N active VMs and a pool of standby VMs that can take over if one or more active VMs fail.
C) There are N active VMs, each one paired with a standby VM that takes over if the active VM fails.
D) There are N active VMs to support the service with additional active VMs to provide extra capacity if one or more VMs fail.