When considering factors that shift demand curves, which of the following would cause a rightward shift in the demand curve for a normal good?

• A. A decrease in the population size
• B. A decrease in the price of a substitute good
• C. A decrease in the price of the good itself
• D. An increase in consumer income

Answer: (D)

Verified step by step guidance

1. Understand that a demand curve shows the relationship between the price of a good and the quantity demanded, holding other factors constant.
2. Recall that a rightward shift in the demand curve means an increase in demand at every price level, not just a movement along the curve.
3. Identify factors that cause shifts in demand, such as changes in consumer income, prices of related goods (substitutes and complements), population size, and consumer preferences.
4. Recognize that for a normal good, an increase in consumer income leads to an increase in demand, shifting the demand curve to the right.
5. Analyze the other options: a decrease in population size would reduce demand (leftward shift), a decrease in the price of a substitute good would reduce demand for the good (leftward shift), and a decrease in the price of the good itself causes movement along the demand curve, not a shift.