WPForms dynamic choices display by category

functions.php

<?php
/**
 * Narrow down post displayed by category.
 *
 * See https://codex.wordpress.org/Template_Tags/get_posts
 *
 * @param array $args
 * @param array $field
 * @param int $form_id
 * @return array
 */
function wpf_dynamic_choices_categories( $args, $field, $form_id ) {

	// For field #4 in form #10, only show entries in category #5
	if ( '10' == $form_id && '2' == $field['id'] ) {
		$args['category'] = '5';
	// For field #2 in form #11, only show entries in category #6
	} elseif ( '11' == $form_id && '2' == $field['id'] ) {
		$args['category'] = '6';
	}

	return $args;
}
add_filter( 'wpforms_dynamic_choice_post_type_args', 'wpf_dynamic_choices_categories', 10, 3 );