How to Hide the "Options Table" Admin Menu

function plt_hide_nhrrob_options_table_manager_menus() {
	//Hide the "Tools → Options Table" menu.
	remove_submenu_page('tools.php', 'nhrotm-options-table-manager');
}

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

Where do I put this code?