Answer:
A. becomes positive once the value of the next best use of resources used in production is included
Explanation:
Economic profit is accounting profit less implicit cost or opportunity cost.
Opportunity cost is the cost of the next best option forgone when one alternative is chosen over other alternatives.
Accounting profit is total revenue less total cost.
If in the short run firms are earning economic profit, in the long run firms would enter into the industry and this would drive economic profit to zero. While economic profit is zero, accounting profit would be postive. So the firm would still be earning accounting profit.
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