JSFiddle - React, Tailwind, and code Playground

HTML

<select multiple='multiple' id="selMulti">
     <option value="1">Option 1</option>
     <option value="2">Option 2</option>
     <option value="3">Option 3</option>
     <option value="4">Option 4</option>    
</select>
<input type="button" id="go" value="Go!" />
<div style="margin-top: 10px;" id="result"></div>

JavaScript

$("#go").click(function(){
     var selMulti = $.map($("#selMulti option:selected"), function (el, i) {
         return $(el).text();
     });
     $("#result").text(selMulti.join(", "));
});