Answer:
C. Substitution effect
Step-by-step explanation:
The substitution effect is the change a consumer makes from one good to another when either of them changes in price. The relationship happens with the so-called substitute goods. These goods have similarities with each other, “competing” in some way for consumer preference. That is, when a good becomes more expensive, the consumer may consider that it is no longer worth buying it. Therefore, it migrates its consumption to a cheaper substitute good. Based on this concept, we can conclude that the substitution effect explains why the idea of Al may not work.