If the price of walnuts rises, many people would switch from consuming walnuts to consuming pecans. But if the price of salt rises, people would have difficulty purchasing something to use in its place. These examples illustrate the importance of

The availability of close substitutes in determining the price elasticity of demand

Explanation:

A good with many close substitutes is likely to have relatively elastic demand, since consumers can easily choose to purchase one of the close substitutes if the price of the good rises.

Unlike a good with no close substitute which tend to have inelastic demand if the price increases, because consumers will have no other option than to either buy it or leave.

answer; curiosity;