Which transceiver type is needed to connect to 40Gb Ethernet networks?

A.
QSFP
B.
CX4
C.
XFP
D.
SFP+
Explanation:
Reference:
http://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_nac03707430&DocLang=en&docLocale=en_US&jumpid=reg_r1002_usen_c-001_title_r0002