Your company has an Active Directory Domain Services (AD DS) domain that runs at the Windows Server 2008 functional level. All domain controllers run Windows Server 2008 R2 (Core Installation). You h ave a Remote Desktop Services infrastructure that includes a Remote Desktop Connection Broker (RD Connection Broker) server and aRemote Desktop Session Host (RD Session Host) server in redirection mode . You configure a virtual machine (VM) as a personal v irtual desktop for an employee. The Personal Virtual Desktop tab is not visible when you display the properties of the employee ¯s user account You need to assign a personal virtual desktop to the user account. What should you do?（）

A. Run the Configure Virtu al Desktops Wizard.
B. Raise the domain functional level to Windows Server 2008 R2.
Configure a virtual desktop pool on the RD Connection Broker server. Add the VM to the pool.
D. Use the Active Directory Users and Computers console on a server that runs W indows Server 2008 R2.