Which of the following best explains public goods?

Public goods are characterized by two main features: non-excludability and non-rivalry. Non-excludability means that individuals cannot be effectively excluded from using the good, and non-rivalry means that one person's use of the good does not reduce its availability to others.

In the case of public goods, they can be consumed by anyone, and one person's consumption does not diminish the quantity or quality available for others. Classic examples of public goods include national defense, public parks, and clean air. These goods remain available to everyone regardless of whether they contribute to their provision or not.

This understanding clarifies why this answer is the most accurate representation of public goods, distinguishing them from private goods or club goods, which are subject to excludability and rivalry.