Your network contains an Active Directory domain.
The domain contains five domain controllers.
A domain controllernamed DC1has the DHCP roleand the file server role installed.
You need to move the Active Directory database on DC1 to an alternate location.
The solution must minimize impact on the network duringthe database move.
What should you do first?

A.
Restart DC1 in Safe Mode.

B.
Restart DC1 in Directory Services Restore Mode.

C.
Start DC1 from Windows PE.

D.
Stop the Active Directory Domain Services serviceon DC1.

Explanation:
http://technet.microsoft.com/en-us/library/cc794895%28v=ws.10%29.aspx
Relocating the Active Directory Database Files
Applies To: Windows Server 2008, Windows Server 2008 R2
Relocating Active Directory database files usually involves moving files to a temporary location whilehardware
updates are being performed and then moving the files to a permanent location. On domain controllers that are
running versions of Windows 2000 Server and WindowsServer 2003, moving database files requires restarting
the domain controller in Directory Services RestoreMode (DSRM). Windows Server 2008 introduces
restartable Active Directory Domain Services (AD DS), which you can use to perform database
management tasks without restarting the domain controller in DSRM. Before you move database files, you
must stop AD DS as a service.