Final answer:
A change in consumer preferences, such as the opinion that rainboots are out of style, leads to a leftward shift in the demand curve, indicating a decrease in demand at every price point.
Step-by-step explanation:
If people decide that rainboots are out of style, this change in tastes and preferences will affect the demand for rainboots. Understanding that the demand curve represents the relationship between the price of an item and the quantity demanded, we can infer that a decrease in the public's preference for rainboots will lead to a leftward shift in the demand curve. This is because, at any given price, consumers are now less willing to purchase rainboots.
Graphically, a leftward shift of the demand curve means that at every price point the quantity demanded decreases. This shift represents a decrease in demand. This type of change is influenced by factors other than price, such as consumer trends, expectations, and changes in income. In this situation, the shift is due to a change in fashion trends.