Which hardware feature is supported on the HP Compaq 615 notebook but not on the Compaq
610 notebook?

A.
AMD processors and chipsets

B.
a Bluetooth option

C.
a Blu-ray disk option

D.
an extended-life battery option

Explanation:
http://laptops-reviewed.com/2009/08/22/hp-compaq-615-laptop-reivew/(first paragraph)