Which of the following examples exemplifies a rivalrous private good?

• A. National defense services
• B. A public park open to everyone
• C. A television broadcast over the airwaves
• D. A slice of pizza purchased at a restaurant

Answer: (D)

Verified step by step guidance

1. Understand the definition of a rivalrous private good: it is a good that is both rivalrous and excludable. Rivalrous means that one person's consumption of the good reduces the amount available for others, and excludable means people can be prevented from using it if they do not pay.
2. Analyze each option to determine if it is rivalrous and excludable. For example, national defense services are non-rivalrous (one person's protection does not reduce protection for others) and non-excludable (everyone benefits regardless of payment).
3. Consider a public park open to everyone: it is generally non-excludable and non-rivalrous up to a point, since many people can use it simultaneously without reducing others' enjoyment.
4. Look at a television broadcast over the airwaves: it is non-rivalrous because one person watching does not reduce availability for others, and often non-excludable because it is freely accessible.
5. Finally, evaluate a slice of pizza purchased at a restaurant: it is rivalrous because once eaten, that slice cannot be consumed by someone else, and excludable because only paying customers can obtain it. This matches the definition of a rivalrous private good.