If a firm experiences constant returns to the variable input in the sh

If a firm experiences constant returns to the variable input in the short run:

A) marginal product will be greater than average variable product, but the two will become more equal as output increases.
B) marginal product will be less than average variable product, but the two will become more equal as output increases.
C) marginal product will be greater than average variable product, and the difference between the two will become larger as output increases.
D) marginal product and average variable product will be equal over the range of output in question.

ANSWER

D