You have a computer that runs Windows Vista (x86). You need to perform a clean installation of Windows 7(64-bit).  What should you do?（）

• A、From the Windows 7 installation media, run Rollback.exe.
• B、From the Windows 7 installation media, run Migsetup.exe.
• C、Start the computer from the Windows 7 installation media. From the Install Windows dialog box, select the Upgrade option.
• D、Start the computer from the Windows 7 installation media. From the Install Windows dialog box, select the Custom (advanced) option.