Final answer:
Marginal utility is the additional satisfaction or happiness from consuming an additional unit of a good or service. It is a key concept in economics that helps explain consumer choice under budget constraints, and it can decrease as more of a good is consumed, a concept known as diminishing marginal utility. The correct option is D.
Step-by-step explanation:
Among the given options, marginal utility is best defined as the additional satisfaction or happiness received from the consumption of an additional unit of a good or service. In economics, utility is a measure of the satisfaction a consumer derives from the consumption of goods and services. The concept of marginal utility plays a crucial role in the consumer choice theory, aiding in understanding how individuals make decisions to achieve the highest level of utility given their budget constraints.
In practical terms, let's suppose José buys a T-shirt for $5 and the utility he gains from this purchase is 10 utils. This would indicate that José receives 2 utils per dollar spent. Now, if the cost remains the same and the additional utility José gets from buying a second T-shirt is 8 utils, the marginal utility of the second T-shirt is 8 utils.
Economists also discuss marginal utility per dollar, which is computed by dividing the additional utility received from an item by its price. For José's T-shirts and movies, a table might show the diminishing marginal utility per dollar, reflecting the principle that as one consumes more and more of a good, the satisfaction from each additional unit tends to decrease. This is known as diminishing marginal utility.