How to Hide the "Qeryz Survey" Admin Menu

function plt_hide_qeryz_microsurvey_tool_menus() {
	//Hide the "Qeryz Survey" menu.
	remove_menu_page('qeryz_survey_admin_page');
}

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

Where do I put this code?