You are installing an application on a computer that runs Windows Server 2008 R2. During  installation， the application will need to add new attributes and classes to the Active Directory  database.     You need to ensure that you can install the application.     What should you do（）

• A、Change the functional level of the forest to Windows Server 2008 R2.
• B、Log on by using an account that has Server Operator rights.
• C、Log on by using an account that has Schema Administrator rights and the appropriate rights to install the applicatio
• D、Log on by using an account that has the Enterprise Administrator rights and the appropriate rights to install the app