The Incentive to Increase Employment When the Economy Is in Recession

The incentive to increase employment when the economy is in recession is given by

A) the vertical gap between labor demand and labor supply at the point of employment.
B) the excess of the marginal product of labor relative to the value of an extra unit of leisure.
C) the low opportunity cost of workers' time in comparison with their marginal productivity on the job.
D) all of the above.
E) none of the above.