参考答案：C

解析：

Economic rent is the difference between the price paid for a resource and its opportunity cost in its next-highest-valued employment. To earn economic rent, a worker must generate a high marginal revenue product. The less elastic its supply curve, the more of the wage is economic rent. Popular entertainers and professional athletes, for example, earn economic rent because their services are valued much more highly in those occupations (high MRP) than they would be in their next-best alternative, and very few people possess their specific skills (inelastic supply).