If fixed costs are $333,000, the unit selling price is $74, and the unit variable costs are $53, what are the old and new break-even points in sales units (rounded to a whole number) if the unit selling price increases by $7?

a. 15,857 units and 11,893 units, respectively

b. 4,500 units and 15,857 units, respectively

c. 6,283 units and 11,393 units, respectively

d. 15,857 units and 4,500 units, respectively