<SCRIPT type="text/javascript"> 
function findButton() {
var myForm = document.forms.animalForm;
var i;
for(i=0;i<myForm.MARSUPIAL.length; i++) {
if(myForm.marsupial[i].checked) {
break;
}
}
alert("You selected ""+myForm.marsupial[i].value+"".");
}
</script>
<form name="animalForm" action="">
<INPUT type="radio" name="marsupial" value="KANGAROO" />Kangaroo
<br /><input type="radio" name="marsupial" value="Opossum" />Opossum
<br /><input type="radio" name="marsupial" value="Tasmanian Tiger" />Tasmanian Tiger
<input type="button" name="GO" value="GO" onclick="findButton()" />

<script type="text/javascript"> 
function findButton() {
var myForm = document.forms.animalForm;
var i;
for(i=0;i<myForm.marsupial.length; i++) {
if(myForm.marsupial[i].checked) {
break;
}
}
alert("You selected ""+myForm.marsupial[i].value+"".");
}
</script>
<form name="animalForm" action="">
<input type="radio" name="marsupial" value="kangaroo" />Kangaroo
<br /><input type="radio" name="marsupial" value="Opossum" />Opossum
<br /><input type="radio" name="marsupial" value="Tasmanian Tiger" />Tasmanian Tiger
<input type="button" name="GO" value="GO" onclick="findButton()" />