Final answer:
The most likely effect on the demand for apples if the price of pears rises is a decrease in demand.
Step-by-step explanation:
The most likely effect on the demand for apples if the price of pears rises is a decrease in demand for apples. This can be explained by the concept of cross-price elasticity, which measures the responsiveness of the demand for one good to a change in the price of another good.
In this case, if apples and pears are substitutes, then an increase in the price of pears would lead consumers to substitute pears with apples. As a result, the demand for apples would increase. Conversely, if the price of pears rises, consumers would be less willing to buy pears and may choose to buy fewer apples, leading to a decrease in the demand for apples.
Therefore, the most likely effect on the demand for apples if the price of pears rises is a decrease in demand.