public function response_settings() {
		if ( ! class_exists( 'INVP' ) ) {
			return array();
		}

		$public_keys = array(
			'use_carfax',
		);

		return array_filter(
			INVP::settings(),
			function ( $k ) use ( $public_keys ) {
				return in_array( $k, $public_keys, true );
			},
			ARRAY_FILTER_USE_KEY
		);
	}