Which HP storage innovation removes allocated but unused space without affecting performance?

A.
HP StoreOnce technology

B.
HP flash-optimized storage technologies

C.
HP Memristor technology

D.
HP thin technologies

Explanation:
http://h20195.www2.hp.com/V2/GetPDF.aspx/4AA3-4024ENW.pdf(page 9, first
bulleted point)