You need to install Windows 2000 Professional on a new computer in your network. You use the Setup Manager wizard to configure a fully automated installation script file. You begin an unattended installation and leave the office.   When you return, the installation has reached the GUI-mode Setup and you see the following error message. “Unattended Setup is unable to continue because a Setup parameter specified by you system administrator or computer manufacturer is missing or invalid.”  You need to complete the installation.  What must you do?（）

• A、 In the Unattended section of the answer file， set the OemPreinstall property to Yes.
• B、 In the NetBinding section of the answer file， specify the Enable variable.
• C、 In the UserData section of the answer file， specify the ProductID variable.
• D、 In the GuiUnattended section of the answer file， set the OemSkipWelcome property to 1