The president of the United States receives an annual salary of $400,000. Derek Jeter, shortstop for the New York Yankees, receives an annual salary of $23.2 million. If the president of the United States actually contributes more to society than Derek Jeter, we can conclude that:
actors other than marginal revenue product probably explain the salary differences.
the salary differences are based entirely on marginal revenue products.
there is never a relationship between marginal revenue product and pay.
the markets for their respective services are perfectly competitive.