Aspen Artifacts sells a single product. 7,000 units were sold resulting in $70,000 of sales revenue, $28,000 of variable costs, and $12,000 of fixed costs.

The number of units that must be sold to achieve $60,000 of operating income is:

A. 10,000 units

B. 11,666 units

C. 12,000 units

D. None of these answers are correct.