问题：

[单选] You need to design an administrative model for Exchange Server 2003. What should you？（）

A . Create an administrative group for each office. Place each Exchange server that is managed by an office technician into that Office’s administrative group. Assign the central IT group full control over all administrative groups. Assign each office technician control over his or her office’s administrative groups
B . Create one administrative group. Place all Exchange servers in the administrative group. Assign the central IT group full control over the administrative group. Make each office technician a member fo the local Backup Operators group on each group they manage
C . Create an administrative group for each office. Place one Exchange server in each group. Assign the central IT group and each office technician full control over each administrative group
D . Create one administrative group for all Exchange front-end servers. Assign each office technician control over this administrative group. Create another administrative group for all Exchange back-end servers. Assign the central IT group control over this administrative grou