What best describes the concept of rivalry in consumption?

The concept of rivalry in consumption refers to the idea that one person's use of a good or service decreases its availability for others. When a good is rivalrous, it means that if one individual consumes the product, there is less of it available for others to consume. This is typical of many private goods, such as food or clothing, where once someone purchases and uses the item, it is no longer available for someone else to use.

For example, if one person eats a slice of pizza, that slice is no longer available for someone else; thus, the use of that good reduces its availability to others. This contrasts with non-rivalrous goods, where one person's consumption does not impact another's ability to consume the same good. Understanding rivalry in consumption is crucial for analyzing how resources are allocated in an economy and the impact of individual consumption on overall availability.