Explanation:
All are benefits of virtualization.
A. Backup and recovery can be centralized at one location, even with world-wide subsidiaries. The management of backup and recovery is therefore centralized and streamlined over 24 hours.
B. Lower operating cost comes from centralized or clustered locations, and for less costs for maintaining and replacing physical machines.
C. Security is vital to a commercial business. Virtualization allows security to conform to uniform standards for all locations without scattered locations supervised / operated by local personnel with different security standards.
D. Streamlining and automated management tasks includes all of the above. There is no more need to schedule availability of particular types of machines at particular locations. All resources are available at any time (assuming proper design of resources). Tasks can therefore be automated with continuous production, hence productivity. This is the most important feature and advantage of virtualization.
E. Ability to run legacy programs is definitely an advantage, but in almost all case, this is an occasional requirement, so is lower in the importance of the advantages.
