Answer: Option (A) is correct.
Step-by-step explanation:
Correct Option: A.supply whatever amount consumers demand at a price determined by the minimum point on the typical firm's average total cost curve.
In the long run, equilibrium price of a perfectly competitive firm implies that there is no economic profit for the firm. This situation occur when the marginal cost is equal to the average total cost.
The firm is break even when the price is equal to the minimum point of average total cost of the firm. So, there is no possibility of economic profit for the firm.