Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<body>

<p>Click the button to create a SELECT and an OPTION element.</p>

<button onclick="myFunction()">Try it</button>

<script>
function myFunction() {
    var x = document.createElement("SELECT");
    x.setAttribute("id", "mySelect");
    document.body.appendChild(x);

    var z = document.createElement("option");
    z.setAttribute("value", "volvocar");
    var t = document.createTextNode("Volvo");
    z.appendChild(t);
    document.getElementById("mySelect").appendChild(z);
}
</script>

</body>
</html>