Which of the Following Statements Is False

Which of the following statements is false?

A) Inefficient work rules that hamper productivity come at the expense of the firm's profits.
B) The firm is indifferent between the various wage/employment combinations that exist along the contract curve.
C) The union prefers higher iso-utility or indifference curves to lower ones.
D) The labour demand curve intersects isoprofit curves at their maximum points.
E) The contract curve does not exist if the product market in which the firm operates is perfectly competitive.