Profit Analysis in Perfect Competition

Which of the following is true when the marginal revenue in a perfectly competitive market falls to a point where the intersection of MR and MC coincides with the ATC curve?

MR = Marginal Revenue

MC = Marginal Cost

ATC = Average Total Cost

1. The firm's profit is on the rise.
2. The firm is incurring losses with each unit sold.
3. The firm's Total Revenue is less than its Total Cost.
4. The firms has reached a point where its Total Revenue = Total Cost.