What is a scalability challenge that vSphere can address?

A.
Change management processes are simplified

B.
Automatic balancing of virtual machines after adding new physical servers

C.
Easier disaster recovery processes

D.
Users have self-service provisioning of virtual machine workloads

Explanation:
http://www.vmware.com/files/pdf/techpaper/Whats-New-VMware-vSphere-51-PlatformTechnical-Whitepaper.pdf(page 12)