If the Product Derived from the Last Dollar Spent on Labor

If the product derived from the last dollar spent on labor is less than the product derived from the last dollar spent on capital, then the firm

A) is minimizing costs.
B) should use more labor and less capital to minimize costs.
C) should use less labor and more capital to minimize costs.
D) should increase the price paid to labor and decrease the price paid to capital to minimize costs.