A user in a branch office of your company attempts to join a computer to the domain, but the
attempt fails.
You need to enable the user to join a single computer to the domain.
You must ensure that the user is denied any additional rights beyond those required to
complete the task.
What should you do?

A.
Prestage the computer account in the Active Directory domain.

B.
Add the user to the Domain Administrators group for one day.

C.
Add the user to the Server Operators group in the Active Directory domain.

D.
Grant the user the right to log on locally by using a Group Policy Object (GPO).

Explanation:
http://technet.microsoft.com/en-us/library/cc770832%28v=ws.10%29.aspx#BKMK_1
Prestaging Client Computers
Benefits of Prestaging Client Computers
Prestaging clients provides three main benefits:
An additional layer of security. You can configure Windows Deployment Services to answer
only prestaged clients, therefore ensuring that clients that are not prestaged will not be able
to boot from the network. Additional flexibility. Prestaging clients increases flexibility by
enabling you to control the following. For instructions on performing these tasks, see the
“Prestage Computers” section of How to Manage Client Computers.
* The computer account name and location within AD DS.
* Which server the client should network boot from.
* Which network boot program the client should receive.
* Other advanced options — for example, what boot image a client will receive or what
Windows Deployment Services client unattend file the client should use.
The ability for multiple Windows Deployment Services servers to service the same network
segment. You can do this by restricting the server to answer only a particular set of clients.
Note that the prestaged client must be in the same forest as the Windows Deployment
Services server (trusted forests do not work).
Further information:
http://www.windows-noob.com/forums/index.php?/topic/506-how-can-i-prestage-a-computerfor-wds/how can I PRESTAGE a computer for WDS?