JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
Select a fruit and click the button:
<select id="mySelect">
    <option value="11">Apple</option>
    <option value="12">Orange</option>
    <option value="13">Pineapple</option>
    <option value="14">Banana</option>
</select>
<button type="button" id="btn">Display index</button>

JavaScript

$('#btn').on('click',function(){
    // var x = document.getElementById("mySelect").selectedIndex;
    //    var y = document.getElementById("mySelect").options;

    var x = $("#mySelect").val();
    var y = $("#mySelect option:selected").text();

    alert(x+" :: "+y);
    //alert("Index: " + y[x].index + " text is " + y[x].text + " and value is " + y[x].value);

});