Answer:
The correct answer is letter "D": incorrect because all inputs are varied in the example.
Step-by-step explanation:
The law of Diminishing Marginal Productivity states that increasing one variable will keep the others the same. My initially increase output but eventually adding more of that one variable may lead to a diminishing rate of return. The law helps explain why increasing production is not always the best way to increase profits.
The law of Diminishing Marginal Productivity only applies when certain inputs are fixed, but in this example, the amount of labor available varies since it is increasing.