What is the purpose of using a VSAN in Cisco Datacenter networking?

A.
Prevents FSPF Loops

B.
Provides a method to prioritize traffic within the Cisco UCS

C.
Creates redundant connections from UCS Fabric Interconnects to Fabric Extenders

D.
Allows the use of a single physical storage infrastructure while maintaining logical separation end-to-end

Explanation:
According to the DCUCD training material, page 6-12:

SAN networking is used to connect server to the central storage. Similarly to VLANs in a data network, VSANs can be used to isolate storage networking thus giving the ability to use a single physical infrastructure while maintaining logical separation end-to-end.