Wonder Company sells Product A for $21 per unit. Wonder'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 $4 per unit for shipping. Wagner 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.$14.

B.$15.

C.$16.

D.$18.