Raptor Company had 11,500 units in its ending inventory on December 31, 2016. During 2016, the companys variable production costs were $8 per unit and its fixed manufacturing overhead rate was $5 per unit. If the companys operating income for 2016 was $13,000 lower under variable costing than it was under absorption costing, how many units were in beginning inventory on January 1, 2016? (Assume the company uses normal costing)

a. 14,100 units

b. 13,125 units

c. 8,900 units

d. 9,875 units

e. 14,000 units

f. 10,500 units

g. 12,500 units

h. None of the above