If marginal product is less than average product, then

A) average product must be increasing.
B) marginal product must be decreasing.
C) marginal product must be increasing.
D) marginal product could either be increasing or decreasing.

Average Product

The output per unit of input, calculated by dividing total production by the number of units of input.

Marginal Product

The additional output that is produced by adding one more unit of a particular input, keeping other inputs constant.