The Marginal Labor Cost Curve for a Monopsonist

The marginal labor cost curve for a monopsonist

A) is equal to the supply curve of labor
B) lies above the supply curve of labor
C) lies below the supply curve of labor
D) is affected by the fact that workers are less willing to work than under conditions of perfect competition
E) is lower than the marginal revenue product of labor in equilibrium which assures the monopsonist a return to monopoly power