Your network contains a Web server that runs Windows Server 2008 R2.
The server contains 10 Web sites.
You need to back up the Microsoft ASP.NET configuration settings of one Web site.
The solution must minimize the size of the backup.

What should you do?

A.
Perform a system state backup.

B.
Copy the Web.config file.

C.
Copy the ApplicationHost.config file.

D.
Copy the %systemdrive%inetpub folder.

Explanation:
In the web content directories, there may be optional web.config files that control the behavior for their level of the hierarchy and downward. They could be local or remote (if the content directory is on a UNC share, for example). They may contain IIS, ASP.NET or any other .NET framework configuration settings that can be specified at their level. By default there are no web.config files.

Source: http://learn.iis.net/page.aspx/282/the-configuration-system-in-iis-7/