You have a Windows Server 2008 R2 Hyper-V server.
One of the virtual machines (VMs) that is hosted on the server has a directly attached physical disk.
You need to back up the VM.
What should you do?

A.
Perform a full server backup on the VM.

B.
Perform a critical-volume backup on the VM.

C.
Perform a full server backup on the host server.

D.
Perform a critical-volume backup on the host server.