Your company has an Active Directory forest that contains only Windows Server 2008 domain controllers.
You need to prepare the Active Directory domain to install Windows Server 2008 R2 domain controllers.
Which two tasks should you perform? (Each correct answer presents part of the solution. Choose two.)

A.
Run the adprep /domainprep command.

B.
Raise the forest functional level to Windows Server2008.

C.
Raise the domain functional level to Windows Server2008.

D.
Run the adprep /forestprep command.