Match the following. List-I List-II a. Increase in demand 1. Leftward shift of the demand curve b. Extension of demand 2. Upward shift of the demand curve c. Decrease in demand 3. Upward movement on the demand curve d. Contraction of demand 4. Downward movement on the demand curve

The correct answer is A. a-2, b-4, c-1, d-3.

• An increase in demand is a rightward shift of the demand curve. This means that at any given price, consumers are willing and able to buy more of the good. This can be caused by a number of factors, such as an increase in income, a decrease in the price of substitutes, or an increase in the expected future price of the good.
• An extension of demand is a movement along the demand curve to a higher quantity demanded. This means that consumers are willing and able to buy more of the good at the same price. This can be caused by a decrease in the price of the good, an increase in income, or an increase in the number of consumers.
• A decrease in demand is a leftward shift of the demand curve. This means that at any given price, consumers are willing and able to buy less of the good. This can be caused by a number of factors, such as a decrease in income, an increase in the price of substitutes, or a decrease in the expected future price of the good.
• A contraction of demand is a movement along the demand curve to a lower quantity demanded. This means that consumers are willing and able to buy less of the good at the same price. This can be caused by an increase in the price of the good, a decrease in income, or a decrease in the number of consumers.