You can let the server determine which RadioButton in a group is selected. At run time, the server compares each checked value you specified to a value in a DataSet. If the values match, the server checks the RadioButton.
For more information on ASP.NET RadioButton properties, see the documentation on the Microsoft website at http://msdn.microsoft.com/library/en-us/cpgenref/html/cpconradiobuttonwebservercontrol.asp.