Which technology provides a backup solution for virtual machines?

You are considering moving from an environment in which each physical server hosts a single
application, and each application is backed up on a specified timeframe. The proposed
environment will consist of virtual machines that perform the role of their physical counterparts.
Your manager is trying to determine the best way to backup these applications once the project is
complete. Which technology provides a backup solution for virtual machines?

A.
Distributed Power Management (DPM)

B.
high Availability (HA)

C.
vCenter

D.
vSphere Data Protection (vDP)

Explanation:
http://www.vmware.com/files/pdf/techpaper/Introduction-to-Data-Protection.pdf