Answer:
Quantity
Step-by-step explanation:
A quantity discount is a dicount that occurs or that is put in place when a least certain amount of goods is ordered or purchased.
Like the question, there is a 15% discount for at least a dozen orders of Mandarin bird feeders. If the order exceeds a dozen peices, say 13 or 14 or 50 or even a 100 pieces, the discount of 15% comes into play during payment for those feeders.
Cheers.