问题：

[单选]

You are the network administrator for your company. The network consists of a single Active  
Directory forest. The forest consists of 19 Active Directory domains. Fifteen of the domains contain  Windows Server 2003 domain controllers. The functional level of all the domains is Windows 2000 native.  The network also consists of a single Microsoft Exchange 2000 Server organization. You need to create  groups that can be used only to send e-mail messages to user accounts throughout the company. You  want to achieve this goal by using the minimum amount of replication traffic and minimizing the size of the  Active Directory database. You need to create a plan for creating e-mail groups for your company. 
What should you do？（）

A .  Create global distribution groups in each domain. Make the appropriate users from each domain members of the global distribution group in the same domain. Create universal distribution groups. Make the global distribution groups in each domain members of the universal distribution groups.
B .  Create global security groups in each domain. Make the appropriate users from each domain members of the security group in the same domain. Create universal security groups. Make the global security groups in each domain members of the universal security groups.
C .  Create universal distribution groups. Make the appropriate users from each domain members of a universal distribution group.
D .  Create universal security groups. Make the appropriate users from each domain members of a universal security group.