20. A single-product company prepares income statements using both absorption and variable costing methods. Manufacturing overhead cost applied per unit produced in 2009 was the same as in 2008. The 2009 variable costing statement reported a profit whereas the 2009 absorption costing statement reported a loss. The difference in reported income could be explained by units produced in 2009 being

a. Less than units sold in 2009.

b. Less than the activity level used for allocating overhead to the product.

c. In excess of the activity level used for allocating overhead to the product.

d. In excess of units sold in 2009.