AP Microeconomics

Answer - C - Marginal resource cost is the amount of cost added to the business by adding one additional unit of labor.

Key Takeaway: The marginal resource cost (often shortened to MRC) is simply the addition to the business’s total cost by adding one more unit of labor. The goal of any business is, obviously, to make money, so the business should hire labor at an additional cost until the units stop contributing to overall revenue.