Frontend.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

/**
 * Captcha image model
 *
 * @author     Magento Core Team <core@magentocommerce.com>
 */
namespace Magento\Captcha\Model\Config\Form;

class Frontend extends \Magento\Captcha\Model\Config\Form\AbstractForm
{
    /**
     * @var string
     */
    protected $_configPath = 'captcha/frontend/areas';
}