The Law of Diminishing Returns, as It Applies to Labor

The law of diminishing returns, as it applies to labor, means that

A) the marginal product of labor eventually declines.
B) the marginal product of labor will eventually be a horizontal line at zero.
C) the average product of labor increases at a decreasing rate.
D) the average product of labor starts to decline before the marginal product of labor.
E) total output eventually decreases.