Your company has 250 branch offices.   Your network contains an Active Directory domain. The domain controllers run Windows Server 2008 R2.   You plan to deploy Read-only Domain Controllers （RODCs） in the branch offices. You need to plan the deployment of the RODCs to meet the following requirements： èBuild each RODC at the designated branch office.   èEnsure that the RODC installation source files do not contain cached secrets.   èMinimize the bandwidth used during the initial synchronization of Active Directory Domain Services （AD？DS）.   What should you include in your plan？（）

• A、Use Windows Server Backup to perform a full backup of an existing domain controller. Use thebackup to build the new RODCs.
• B、Use Windows Server Backup to perform a custom backup of the critical volumes of an existing domain controller. Use the backup to build the new RODCs.
• C、Create a DFS namespace that contains the Active Directory database from one of the existing domain controllers. Build the RODCs by using an answer file.
• D、Create an RODC installation media. Build the RODCs from the RODC installation media.