Your network contains an Active Directory forest. All domain controllers run Windows Server 2008  <br /> Standard. The functional level of the domain is Windows Server 2003.  You have a certification authority (CA).  <br /> The relevant servers in the domain are configured as shown in the following table.  Server name  Operating system  Server role  <br /> Server1  Windows Server 2003  Enterprise root CA  Server2  Windows Server 2008  Enterprise subordinate CA   <br /> Server3  Windows Server 2008 R2   <br /> Web Server  <br /> You need&e
A、Upgrade Server1 to Windows Server 2008 R2.
B、Upgrade Server2 to Windows Server 2008 R2.
C、Raise the functional level of the domain to Windows Server 2008.
D、Install the Windows Server 2008 R2 Active Directory Schema updates.