Which of the following is true regarding backups created with Vmware Data Recovery?

A.
Backups of ESX 3.x VMs take longer than backups of ESX 4 VMs

B.
Backups of ESX 3.x and later VMs take the same amount of time to complete

C.
Backups of ESX 3.x VMs are not supported

D.
Backups of ESX 3.0 VMs are not supported, but ESX 3.5 VMs are supported

Explanation:
VMware Data Recovery Administration Guide Data Recovery 1.1, page 8.

For virtual machines created in vSphere 4.0, the Data Recovery appliance creates a quiesced snapshot of the virtual machine during the backup. The backups use the changed block tracking functionality on the ESX hosts.
For each virtual disk being backed up, it checks for a prior backup of the virtual disk. It uses the change-tracking functionality on ESX hosts to obtain the changes since the last backup. The deduplicated store creates a virtual full backup based on the last backup image and applies the changes to it.

NOTE These optimizations do not apply to virtual machines created with VMware products prior to vSphere
4.0. For example, change tokens are not used with virtual machines created with Virtual Infrastructure 3.5 or
earlier. As a result, virtual machines created with earlier VMware versions take longer to back up