A customer has purchased a 4-node N8500 clustered NAS storage system. The enterprise-edition engine
nodes have two CPUs, 10GE network ports, and 48 GB cache. The performance of an engine node reaches
700 MB/s. The back-end storage uses the S5600T, which is configured with 80 SAS disks divided into eight 9-
disk RAID 5 groups. Each RAID group has one hot spare disk. The performance of each SAS disk in the 9-disk
RAID 5 groups is 30 MB/s. According to the preceding information, what is the overall performance of the
N8500 without considering other factors?

A.
700 MB/s

B.
2800 MB/s

C.
1920 MB/s

D.
2400 MB/s