If Labor Supply of Unskilled Workers Is Perfectly Inelastic, Then

If labor supply of unskilled workers is perfectly inelastic, then

A) firms face an increasing marginal cost of hiring unskilled labor.
B) firms face a horizontal value of marginal product of employment curve.
C) the labor supply curve of unskilled workers is horizontal at the market-clearing wage.
D) the labor supply curve of unskilled workers is vertical at the total number of unskilled workers in the market.
E) workers will supply more hours of labor to the market when wages increase.