You need to configure AD RMS to enable users to use it and protect their documents

Company has a server with Active Directory Rights Management Services (AD RMS) server
installed. Users have computers with Windows Vista installed on them with an Active
Directory domain installed at Windows Server 2003 functional level.
As an administrator at Company, you discover that the users are unable to benefit from AD
RMS to protect their documents.
You need to configure AD RMS to enable users to use it and protect their documents.
What should you do to achieve this functionality?

A.
Configure an email account in Active Directory Domain Services (AD DS) for each user.

B.
Add and configure ADRMSADMIN account in local administrators group on the user
computers

C.
Add and configure the ADRMSSRVC account in AD RMS server’s local administrator
group

D.
Reinstall the Active Directory domain on user computers

E.
All of the above

Explanation:
http://technet.microsoft.com/en-us/library/cc753531%28v=ws.10%29.aspx

AD RMS Step-by-Step Guide
For each user account and group that you configure with AD RMS, you need to add an email address and then assign the users to groups.