Why is the SAS Controller Upgrade module available only for HP Z420 and HP Z620 workstations
and not available for HP Z320 workstations?

A.
Because HP Z320 workstations do not support Microsoft Windows Vista, which is required for
SAS

B.
Because HP Z820 workstations have an integrated LSI SAS 2308 controller

C.
Because HP Z820 workstations already have the SAS Controller Upgrade module preinstalled

D.
Because HP Z820 workstations do not support SAS functionality