How to Hide the "Advanced Google reCAPTCHA" Admin Menu

function plt_hide_advanced_google_recaptcha_menus() {
	//Hide the "Settings → Advanced Google reCAPTCHA" menu.
	remove_submenu_page('options-general.php', 'wpcaptcha');
}

add_action('admin_menu', 'plt_hide_advanced_google_recaptcha_menus', 11);

Where do I put this code?