Simple Quiz Concept using JavaScript

< html xmlns="http://www.w3.org/1999/xhtml"  >
< head runat="server" >
    < title > Untitled Page< /title >
    < script >
    function Test1()
    {
    var q1=document.getElementById("RadioButton1").checked;
    var q2=document.getElementById("RadioButton1").checked;
    var q3=document.getElementById("RadioButton1").checked;
    if(q1==true || q2==true || q3==true)
    {
    document.getElementById("RadioButton1").disabled = true; 
    document.getElementById("RadioButton2").disabled = true; 
    document.getElementById("RadioButton3").disabled = true; 
    document.getElementById("bt1").disabled = true; 
    }
    }
    < /script > 
< /head >
< body >
    < form id="form1" runat="server" >
    1.Which Software Type Foxrpo?< br / >
        < br / >
    < asp:RadioButton ID="RadioButton1" runat="server" GroupName="GltAmt" Text="Application"  / >
           < asp:RadioButton ID="RadioButton2" runat="server" GroupName="GltAmt" Text="Package"  / >
             
    < asp:RadioButton ID="RadioButton3" runat="server" GroupName="GltAmt" Text="Language"   / >
        < br / >
        < br / >
        < br / >
    
    < input type ="button" runat ="server" value ="Click Answer" 
    onclick ="Test1();" 
    id="bt1" / >
   
    < /form >
< /body >
< /html >