JSFiddle - React, Tailwind, and code Playground

HTML

<div class="options a" >
  <input type="checkbox" class='roles' />
     <input type="checkbox" class='roles' />
     <input type="checkbox" class='roles' />
     <input type="checkbox" class='roles' />
</div>
<div class="options b" >
  <input type="checkbox" class='roles' />
  <input type="checkbox" class='roles' />
  <input type="checkbox" class='roles' />
  <input type="checkbox" class='roles' />
</div>

JavaScript

$('.a').children('input[type="checkbox"]').each(function () {
        this.checked = true; 
        });