Joe's Mart policy is to have 20% of the next month's sales on hand at the end of the current month. Projected sales for August, September, and October are 25,000 units, 20,000 units, and 30,000 units, respectively. How many units must be purchased in September?

A.

16,000.

B.

17,000.

C.

22,000.

D.

26,000.

E.

28,000.