A Firm Can Maximize Profit (Net Benefit) by Choosing to Produce

A firm can maximize profit (net benefit) by choosing to produce that level of output at which

A) the difference between the additional revenue from the last unit sold and the additional cost of that unit is maximized.
B) the additional revenue from the last unit sold equals the additional cost of that unit.
C) the additional revenue from the last unit sold is just a little more than the additional cost of that unit.
D) total revenue equals total cost.
Questions 30 through 33 refer to the following:
A clinic uses doctors and nurses optimally and is servicing the maximum number of patients given a limited annual payroll. The last doctor hired treated 1,600 extra patients in a year, while the last nurse hired treated 1,000 extra patients in a year.