You and two partners start a company. However, your partners play no role in running the company. You spend all your time managing the business. The time that you could have spent working for someone else and earning wages instead of running the business is your:

a. Explicit costs

b. Marginal cost

c. Sunk cost

d. Opportunity cost

The correct answer is letter "D": Opportunity cost.

Explanation:

Opportunity cost is described as the return of the choice selected over the potential return that could have been obtained from the choice left behind. It represents the return of the option chosen compared to the choice forgone. Opportunity costs is also defined as the return of the best next available option.