How could the company BEST reduce power consumption among these four servers, while not sacrificing functionality?

A small business currently has four separate servers, three of which perform low-overhead tasks with small memory footprints. How could the company BEST reduce power consumption among these four servers, while not sacrificing functionality?

A.
Enable each server’s Cool ‘n’ Quiet and/orSpeedStep functionality so that processing power is conserved.

B.
Enforce auto-shutdown routines on all four servers for after-hours power saving while the office is closed.

C.
Consolidate the four servers onto the best two, combining them logically by tasks and memory consumption.

D.
Consolidate the four servers onto the most powerful machine using virtualization.