In some industries, the labor productivity of union workers exceeds the labor productivity of nonunion workers. Which of the following might help explain the higher productivity of union workers? Check all that apply. Higher union wage rates allow companies to attract more highly skilled workers. Unions are always more efficient than firms at discerning which workers are highly skilled and which are not. Because union wages exceed nonunion wages, union workers are less likely to quit, which leads to a more experienced work force. O Labor unions enable workers to voice concerns about working conditions and safety issues, making them more confident and less intimidated by their employers and thus more productive