Final answer:
If a person's taste for tacos diminishes, their Marginal Utility curve would flatten out given that each additional taco eaten provides less satisfaction, and the Total Utility curve would shift downward because the overall satisfaction derived from consuming tacos is reduced.
Step-by-step explanation:
The question involves the concept of diminishing marginal utility and how it impacts taste for a particular good, in this case, tacos. A diminished taste for tacos implies that the satisfaction or utility obtained from each additional unit consumed is reduced. Therefore, if a person's taste for tacos diminishes, the most accurate effect on their MU (Marginal Utility) and TU (Total Utility) curves would be option b) the MU curve would get flatter. This is because each additional taco consumed brings less additional satisfaction than before, indicating a decrease in the slope of the MU curve, though it wouldn't collapse to the horizontal axis as the utility, although reduced, is still likely to be positive. The TU curve, which represents the accumulated satisfaction from consumption, would shift downward since the total utility received from a given number of tacos would now be lower due to the diminished taste.