A mainframe customer would like to receive a proposal for a mainframe storage system with 120 TB raw capacity. The 
mainframe server load is not too high， and they need hard disk drives with the lowest possible power consumption to keep operating costs low. The customer will notincrease the capacity of their mainframe applications in the future but rather invest later into their System p servers. 
Which of the following solutions best meets these requirements at the lowest cost（）

A customer has the following non-virtualized servers： - three Exchange servers， each with 2.8 TB database 
- five System i Domino servers， each with 2 TB database 
- 20 TB usable capacitySun/SAP cluster 
- 70 TB usable capacity of System p requirement 
- annual growth rate of 12 TB usable capacity per year  
What is the most cost-effective solution for three years（）