What is the substance used for cooling in the optional liquid cooling system?

A.
72% purified mineral spirits, 25% denatured alcohol, and 3% ethyl alcohol

B.
72% proylene glycol, 25% water, and 3% other

C.
72% pure water. 25% proylene glycol, and 3% other

D.
Pure distilled water

Explanation:
http://h20331.www2.hp.com/Hpsub/downloads/Liquid_Cooling_HP_Z420_Z820_Workstations.pdf