You work as a network exchange administrator at company.com.the company.com network currently consists of a single active directory forest named company.com containing three sites named kingsite1， kingsite2 and kingsite3.thecompany.com organization makes use of microsoft exchange server 2007 service pack 1 （sp1） as their messaging solution.company.com has additionally configured each site with two client access server， mailbox server and hub transport server.during the course of the business week you receive instruction from company.com to install microsoft exchange server 2010 in kingsite1 whilst ensuring that you use the least amount of administrative effort. What should you do？（）

A. you should consider installing service pack 2 （sp2） on all microsoft exchange server 2007 computers in the organization.
B. you should consider installing service pack 2 （sp2） on all microsoft exchange server 2007 computers in kingsite1.
C. you should consider installing service pack 2 （sp2） on all mailbox servers in the organization.
D. you should consider installing service pack 2 （sp2） on all hub transport servers in the organization.
E. you should consider installing service pack 2 （sp2） on all client access servers in the organization.