Answer:
The correct answer is letter "A": consuming an additional unit of a good.
Step-by-step explanation:
Utility represents the satisfaction perceived by an individual while consuming a good or service. Marginal utility reflects the satisfaction the individual perceives by consuming one more unit of the same good or service. Total utility represents the aggregate satisfaction of consuming a given product.
In all cases, the concept of utility assumes consumers make rational decisions to maximize the benefits they perceive and that the products consumed have a stable price.