Final answer:
With increased income, consumers face new budget constraints and may adjust their consumption choices based on personal preferences, as reflected in their indifference curves. Manuel prefers to spend on movies and Natasha on yogurts, demonstrating subjective utility maximization.
Step-by-step explanation:
When income levels rise, consumers' budget constraints shift, allowing them to make new choices regarding consumption. In the case of Manuel and Natasha, both decide to allocate their increased budget differently based on their preferences, which are shown in their indifference curves. If the products in question are normal goods, consumers will generally purchase more of those goods when their income level increases. However, the amount they purchase will vary from person to person. If instead, they are dealing with an inferior good, the consumption of that good might decrease despite the increase in income.
For Manuel, his preference leads him to spend more on movies, while for Natasha, she prefers to spend additional funds on yogurts. This divergence in spending demonstrates the subjective nature of utility maximization, where individuals value products differently even under the same budgetary changes.