The correct answer is A. price elasticity of demand.
Price elasticity of demand is a measure of how much the quantity demanded of a good or service responds to a change in its price. It is calculated by dividing the percentage change in quantity demanded by the percentage change in price.
A price elasticity of demand of less than 1 indicates that demand is inelastic, meaning that a change in price will have a relatively small effect on the quantity demanded. A price elasticity of demand of greater than 1 indicates that demand is elastic, meaning that a change in price will have a relatively large effect on the quantity demanded.
Income elasticity of demand is a measure of how much the quantity demanded of a good or service responds to a change in income. It is calculated by dividing the percentage change in quantity demanded by the percentage change in income.
Cross elasticity of demand is a measure of how much the quantity demanded of one good or service responds to a change in the price of another good or service. It is calculated by dividing the percentage change in quantity demanded of the first good or service by the percentage change in the price of the second good or service.
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