How Does the Theory of Efficiency Wages Explain Above-Equilibrium Wages

Multiple Choice

How does the theory of efficiency wages explain above-equilibrium wages

A) Employers are forced to pay higher wages in efficient markets.
B) Employers give their workers a higher wage in the hope that it will lead to increased productivity.
C) Workers get a raise in wage when they prove they are increasing their productivity.
D) Workers demand higher wages to compensate for poor fringe benefits.