Doon Company incurred the following costs while producing 520 units: direct materials, $7 per unit; direct labor, $23 per unit; variable manufacturing overhead, $20 per unit; total fixed manufacturing overhead costs, $8,840; variable selling and administrative costs, $3 per unit; total fixed selling and administrative costs, $5,200. There are no beginning inventories. What is the unit product cost using variable costing? A. $67 per unit B. $53 per unit C. $80 per unit D. $50 per unit