Tryit Editor v2.9

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

Select your favorite fruit:
<select>
  <option id="myOption" value="apple">Apple</option>
  <option value="orange">Orange</option>
</select>

<p>Click the button to change the value of the apple option.</p>

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

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

<script>
function myFunction() {
    document.getElementById("myOption").value = "newValue";
    document.getElementById("demo").innerHTML = "The value of the value attribute of the 'apple' option has been changed from 'apple' to 'newValue'.";
}
</script>

</body>
</html>