system.xml

<?xml version="1.0"?>
<!--
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
-->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Config:etc/system_file.xsd">
    <system>
        <section id="customer">
            <group id="captcha" translate="label" type="text" sortOrder="110" showInDefault="1" showInWebsite="1" showInStore="0">
                <field id="forms" translate="label comment" type="multiselect" sortOrder="3" showInDefault="1" showInWebsite="1" showInStore="0" canRestore="1">
                    <comment>CAPTCHA for "Create user", "Forgot password", "Payflow Pro" forms is always enabled if chosen.</comment>
                </field>
            </group>
        </section>
    </system>
</config>