JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>

<body>
<script type="text/javascript">
  /*var test = "Hello";
document.getElementById("mytext").value = test;
  */
  
function myFunction() {
	
	var resultado;
    var c1 = document.getElementById("mySelect").value;
	var c2 = document.getElementById("mySelect2").value;
	var c3 = document.getElementById("mySelect3").value;
    if(c1 == "nao" , c2 == "nao" , c3 == "nao" ){
		resultado = 1;
		
	}
	
	else if(c1 == "nao" , c2 == "nao" , c3 == "sim" ){
		resultado = 2;
		
	} 
	
	else if
	
	(c1 == "nao" , c2 == "sim" , c3 == "sim" ){
		
		resultado = 3;
	}
	
	else {
		resultado = 4;
	}
       document.getElementById("demo").innerHTML = resultado;
    
	}



</script>
</script>


<form action="fb.php" method="POST">

 <select name="test" id="mySelect" onchange="myFunction()">
 <option value="selecione">selecione...</option>
 <option value="sim">sim</option>
<option value="nao">nao</option>
<option value="jim">jim</option>

</select>
<select name="test" id="mySelect2" onchange="myFunction()">
<option value="selecione">selecione...</option>
 <option value="sim">sim</option>
<option value="nao">nao</option>

</select>
<select name="test" id="mySelect3" onchange="myFunction()">
<option value="selecione">selecione...</option>
 <option value="sim">sim</option>
<option value="nao">nao</option>

</select>

<p id="demo"></p>
</body>
</html>