Intel Hired a Consultant Who Found That the Value of Marginal

Intel hired a consultant who found that the value of marginal product of Intel's workers decreased as more workers were hired. Suppose Intel is a monopolistically competitive firm. Then the value of marginal product decreases because the I. workers' marginal product of labor decreased as more workers were hired.
II) marginal revenue of Intel's chips decreased as more chips were sold.

A) I only
B) II only
C) Both I and II
D) Neither I nor II