Which storage system combination is supported in a 4-node cluster?

A.
A pair of FAS3270s and a pair of FAS3020s
B.
A pair of FAS3270s with a FAS3240 and a FAS6240
C.
A pair of FAS6280s and a pair of E7900s
D.
A pair of FAS6280s and a pair of FAS3240s
Explanation:
http://www.slideshare.net/netapp/ar-scinetappontap811scaleoutv016-copy
(See page 3, 4)