ABC Company sells Product A for $21 per unit. ABC's unit product cost based on the full capacity of 200,000 units is as follows: Direct Materials $4 Direct Labour $5 Manufacturing Overhead $6 Unit Product Cost $15 A special order offering to buy 20,000 units has been received from a foreign distributor. The only selling costs that would be incurred on this order would be $3 per unit for shipping. ABC has sufficient idle capacity to manufacture the additional units. Two-thirds of the manufacturing overhead is fixed and would not be affected by this order. Assume that direct labour is an avoidable cost in this decision. In negotiating a price for the special order, what should be the minimum acceptable selling price per unit? a. $18 b. $14 c. $15 d. $16