What does cross-elasticity of demand evaluate?

Cross-elasticity of demand specifically measures the responsiveness of the quantity demanded of one good when the price of another good changes. This concept is particularly useful in understanding the relationship between two products, especially if they are substitutes or complements. When the price of one product changes, the cross-elasticity of demand indicates how much the demand for the other product will increase or decrease as a result.

In the case of substitutes, an increase in the price of one product typically leads to an increase in the demand for its substitute, demonstrating a positive cross-elasticity. For complements, an increase in the price of one product often leads to a decrease in the demand for its complement, resulting in a negative cross-elasticity. Therefore, the correct choice highlights the evaluation of price changes across multiple products, which is at the core of understanding market dynamics and consumer behavior in relation to pricing strategies.