What two steps would best harden an Oracle VM Server installation?

What two steps would best harden an Oracle VM Server installation?

A.
Avoid installing additional software in dom0.

B.
Enable firewalling in dom0.

C.
Install virus checking software in dom0.

D.
Use Trusted Computing Modules for Xen0.

E.
Do not share physical network cards between hosts that are on a different subnet.