How to Hide Acumulus Admin Menus

function plt_hide_acumulus_menus() {
	//Hide "Settings → Acumulus settings".
	remove_submenu_page('options-general.php', 'acumulus_settings');
	//Hide "Settings → Acumulus mappings".
	remove_submenu_page('options-general.php', 'acumulus_mappings');
	//Hide "Settings → Activate Pro-support for your Acumulus webshop connector".
	remove_submenu_page('options-general.php', 'acumulus_activate');
	//Hide "Settings → Apply for a free trial account for Acumulus".
	remove_submenu_page('options-general.php', 'acumulus_register');
}

add_action('admin_menu', 'plt_hide_acumulus_menus', 901);

Where do I put this code?