Marginal thinking is best demonstrated by: a. measuring all of the costs of a meal against all of the benefits when deciding whether to order a second milkshake b. deciding to never purchase a coat made with animal skins or furs c. choosing to spend one more hour studying economics because you think the improvement in your score on the next quiz will be worth the sacrifice of time. d. acquiring the information relevant to a choice before making that choice

c. Choosing to spend one more hour studying economics because you think the improvement in your score on the next quiz will be worth the sacrifice of time

Explanation: The word marginal means evaluating the benefits of an activity over the cost of doing that activity. In other word, it requires the individuals to weigh the benefits of doing something over its cost.  If the benefits exceed cost it is best to do that activity. So, choosing to spend one more hour studying economics because you think the improvement in your score on the next quiz will be worth the sacrifice of time involves marginal thinking.

income increases, enabling consumers to buy more goods and services. ( c.)