What is a primary consideration for purchasing an All-in One Smart Zero Client?

A.
Data transfer rate

B.
Power efficiency

C.
Small screen size

D.
Small footprint

Explanation:
http://www.hp.com/hpinfo/newsroom/press_kits/2012/ppsinfluencersummit2012/HP_t41
0_AiO.pdf(page 1)