You manage a server that runs Windows Server 2008. The Windows Backup and Restore utility is installed on the server.You need to create a full backup of all system state data to the DVD drive （R： drive） on the server.Which command should you run on the server？（）

• A、Wbadmin enable backup -addtarget：R： /quiet
• B、Wbadmin enable backup  addtarget：C:// /quiet
• C、Wbadmin start backup  allCritical  backuptarget：C:///quiet
• D、Wbadmin start backup  allCritical  backuptarget：R：/quiet