Under which of the following scenarios would a park be considered a common resource?

• A. The park is maintained by a private company and only accessible to employees of that company.
• B. The park is privately owned and fenced off, with no public access allowed.
• C. The park charges a high entrance fee and limits access to a small group of members.
• D. The park is open to the public and anyone can enter, but excessive use leads to overcrowding and deterioration.

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the definition of a common resource. A common resource is a good that is rivalrous but non-excludable. Rivalrous means one person's use reduces availability for others, and non-excludable means it is difficult or impossible to prevent people from using it.
2. Step 2: Analyze each scenario in terms of excludability and rivalry. For example, if the park is maintained by a private company and only accessible to employees, it is excludable and likely not a common resource.
3. Step 3: Consider the scenario where the park is privately owned and fenced off with no public access. This is clearly excludable and not a common resource.
4. Step 4: Evaluate the case where the park charges a high entrance fee and limits access to a small group. This again is excludable and not a common resource.
5. Step 5: Identify the scenario where the park is open to the public (non-excludable) but excessive use leads to overcrowding and deterioration (rivalrous). This matches the definition of a common resource.