Which of the following variables, when changed, will cause the market demand curve for a product to shift?

• A. Production technology
• B. The price of the product itself
• C. Quantity supplied
• D. Consumer income

Answer: (D)

Verified step by step guidance

1. Understand that the market demand curve shows the relationship between the price of a product and the quantity demanded by consumers, holding other factors constant.
2. Recognize that a change in the price of the product itself causes a movement along the demand curve, not a shift of the curve.
3. Identify that variables which cause the demand curve to shift are factors other than the product's own price, such as consumer income, tastes, prices of related goods, expectations, and number of buyers.
4. Note that production technology and quantity supplied are related to the supply side of the market, so changes in these variables affect the supply curve, not the demand curve.
5. Conclude that a change in consumer income affects consumers' purchasing power and preferences, leading to a shift in the market demand curve either to the right (increase) or left (decrease).