You are implementing an ASP.NET Web site. The site uses a component that must be dynamically configured before it can be used within site pages. You create a static method named SiteHelper.Configure that configures the component. You need to add a code segment to the Global.asax file that invokes the SiteHelper.Configure method the first time， and only the first time， that any page in the site is requested. Which code segment should you use？ （）

• A、void Application_Start（object sender， EventArgs e） { SiteHelper.Configure（）； }
• B、void Application_Init（object sender， EventArgs e） { SiteHelper.Configure（）； }
• C、void Application_BeginRequest（object sender， EventArgs e） { SiteHelper.Configure（）； }
• D、Object lockObject = new Object（）； void Application_BeginRequest（object sender， EventArgs e） { lock（lockObject（）） { SiteHelper.Configure（）； } }