The Figure Below Shows the Supply Curve for Labor

The figure below shows the supply curve for labor.Figure 16.1

-The marginal ​revenue product is:

A) ​the value of all the final goods and services produced by a firm.
B) ​the value that an worker contributes to a firm.
C) ​an increase in the profit of a firm with an increase in the output by one unit.
D) ​the output per unit of worker employed by a firm.
E) ​the value that all the unskilled workers contribute to a firm.