How to Hide the "FormSpammerTrap for Comments Settings" Admin Menu

function plt_hide_formspammertrap_for_comments_menus() {
	//Hide the "Settings → FormSpammerTrap for Comments Settings" menu.
	remove_submenu_page('options-general.php', 'fst4c_settings_options_page');
}

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

Where do I put this code?