Your network consists of a single Active Directory domain. You have a terminal server that runs Windows Server 2003 Service Pack 2 (SP2). You need to prevent users from establishing multiple Remote Desktop connections to the server. What should you do? （）

A. Install and configure Terminal Server Licensing.
B. From Terminal Services Manager, modify the user sessions.
C. From Terminal Services Configuration, modify the server settings.
D. From Active Directory Users and Computers, modify the Sessions settings for each user account.