Answer:
D. making a choice at the margin
Explanation:
According to my research on different decision making methodology, I can say that based on the information provided within the question your decision is an example of making a choice at the margin. These types of choices are choices that involve any sort of addition or subtraction from current conditions, instead of decisions that are one or the other. Since you had to move your time between two choices then we can say this is the answer.
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