JSFiddle - React, Tailwind, and code Playground

HTML

<select id="mySelect">
    <option>Foo0</option>
    <option seleted="selected">Foo1</option>
    <option>Foo3</option>
    <option>Foo4</option>
    <option>Foo5</option>
    <option>Foo6</option>
</select>

JavaScript

jQuery(document).ready(function($){
   var index = $('#mySelect').prop('selectedIndex'); 
    var select = $('#mySelect');
   select.change(function(e){
       alert(index)
     var conf = confirm('Are You Sure?');
     if(!conf){
             $('#mySelect').prop('selectedIndex',index);
         // reset the select back to previous
         return false;
     }
       else{
       index= $('#mySelect').prop('selectedIndex');}

     // do stuff

  });
});