You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You write the following code segment to create a class named MultimediaDownloader that implements the IHttpHandler interface：   namespace Contoso.Web.UI  {  public class MultimediaDownloader ： IHttpHandler   {  // ...  }  }   The MultimediaDownloader class performs the following tasks： it returns the content of the multimedia files from the Web server it processes requests for the files that have the .media file extension   The .media file extension is mapped to the aspnet_isapi.dll file in Microsoft IIS 6.0.  You need to configure the MultimediaDownloader class in the Web.config file of the application. Which code fragment should you use？ （）

• A、A
• B、B
• C、C
• D、D