A virtual machine requires a 4TB disk for application data. The storage administrator has already
created and presented a 4TB LUN to an ESXi 5.x host. The host is currently configured with a
single 500GB VMFS5 datastore.
What is the next step the vSphere administrator must use to provision the data disk?

A.
Create a virtual compatibility mode RDM mapping to the 4TB LUN.

B.
Create a physical compatibility mode RDM mapping to the 4TB LUN.

C.
Expand the existing VMFS volume to 4TB. Create a physical compatibility mode RDM mapping
to the 4TB LUN.

D.
Expand the existing VMFS volume to 4TB. Create a virtual compatibility mode RDM mapping to
the 4TB LUN.

Explanation:
http://sostech.wordpress.com/2011/08/12/vsphere5-storage-import-a-4tb-lun/