Which of the following would cause the demand curve for a good to shift from point A to point B?

• A. A change in the quantity demanded due to a movement along the curve
• B. A decrease in the price of the good itself
• C. A reduction in production costs for the good
• D. An increase in consumer income (assuming the good is normal)

Answer: (D)

Verified step by step guidance

1. Understand the difference between a movement along the demand curve and a shift of the demand curve. A movement along the curve happens when the price of the good changes, affecting quantity demanded, while a shift means the entire demand curve moves due to factors other than the good's own price.
2. Identify that a change in the quantity demanded due to a movement along the curve is caused by a change in the price of the good itself, not by other factors. This means the demand curve does not shift, only the point on the curve changes.
3. Recognize that a decrease in the price of the good itself causes a movement along the demand curve, not a shift. This is because the demand curve shows the relationship between price and quantity demanded, holding other factors constant.
4. Note that a reduction in production costs affects the supply side, not the demand side. This would shift the supply curve, not the demand curve.
5. Understand that an increase in consumer income (assuming the good is normal) increases consumers' purchasing power, causing the demand curve to shift to the right. This means at every price, consumers demand more of the good, which is a shift from point A to point B on the demand curve.