Answer:
C. $21,000
Step-by-step explanation:
Economic profit is accounting profit less implicit cost or opportunity cost.
Opportunity cost is the next best option forgone when one alternative is chosen over other alternatives.
The next best option for the sole proprietor took is to work at the large firm. Thus her opportunity cost is $35,000.
If the capital wasn't used in setting up the business, it would have earned $22,000. This amount is its opportunity cost.
Total opportunity cost = $22,000 + $35,000 =$57,000
Accounting profit = $78,000 - $57,000 = $21,000
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