Which of the following is true regarding the relationship between the productivity of variable production input(s) and their cost to use in a short-run production process? Question 8 options: As the marginal productivity of the input decreases, marginal cost decreases As the marginal productivity of the input decreases, average cost decreases As the marginal productivity of the input decreases, marginal cost increases As the marginal productivity of the input increases, marginal cost remains constant