Your computer runs Microsoft Windows XP Professional. The computer has the following hardware configuration： 512 MB of RAM 1-GHz processor 60-GB hard disk 15 GB of free space 64-MB video adapter. You perform a clean install of Microsoft Windows Vista. You need to ensure that Microsoft Windows Aero Experience is supported. What should you do？（）

A. Upgrade the memory to 1 GB of RA
B. Upgrade the hard disk to 120 GB with 40 GB of free space.
C. Install a video adapter that has 128 MB of RAM， support for Microsoft DirectX 9， and Microsoft Pixel Shader 2.0.
D. Install a video adapter that has 128 MB of RAM， support for Microsoft Scalable Link Interface （SLI） and Microsoft Pixel Shader 2.0.