In the last provided sample, I have used the ImageUrl to access the items, regarding the selection of the RadioButtonList. Since you could not set the visibility of a certain item at server-side with the Visible
property, I have demonstrated you how to achieve the same results with adding a "display:none" style at client-side. Please take a look at the last provided sample, where a JQuery is used to locate the RadListBoxItems with certain ImageUrl properties set.
the Telerik team
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to their blog feed