The correct answer is: D. Elasticity of Demand
Elasticity of demand is a measure of how responsive the quantity demanded of a good is to a change in its price. It is calculated as the percentage change in quantity demanded divided by the percentage change in
price.A demand curve is said to be elastic if the quantity demanded changes by a large percentage in response to a small percentage change in price. A demand curve is said to be inelastic if the quantity demanded changes by a small percentage in response to a large percentage change in price.
The law of demand states that, all other things being equal, the quantity demanded of a good will decrease as the price of the good increases. The law of supply states that, all other things being equal, the quantity supplied of a good will increase as the price of the good increases.
Equilibrium price is the price at which the quantity demanded of a good is equal to the quantity supplied of the good.
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