JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <select name="sel">
        <option value="1">First</option>
    </select>
</form>
<div id="counter"></div>

JavaScript

var query = ":checked";
var $frm = $("form:eq(0)");

var $result = $(query, $frm);

$("#counter").text("Element count: " + $result.length);