JSFiddle - React, Tailwind, and code Playground

HTML

<select class="founder_designation" rel="Designation" placeholder="Designation" multiple="multiple" name="designation">
<option value="">-- Select Designation --</option>
<option value="chairman_managing_director">Chairman &amp; Managing Director</option>
<option selected="selected" value="director" >Director</option>
<option value="whole_time_director">Whole Time Director</option>
<option value="other">Other</option>
</select>

JavaScript

$('.founder_designation').on('click','option',function(){
    
    alert("clicked value:"+$(this).val());

    $a=$('.founder_designation option:selected');
    $str='';
    for($i=0;$i<$a.length;$i++){
        $str+=$('.founder_designation option:selected:eq('+$i+')').val()+",";
    }
    
    alert("all selected :"+$str);
});