Which of the following is a required option for Pest Control Alternatives under Sustainable Sites?

The choice to keep all exterior wood at least 12" above soil is a required option for Pest Control Alternatives under Sustainable Sites because it helps to prevent pest infestations. By elevating wood components, such as decks and siding, the risk of moisture accumulation and direct contact with soil is reduced, which discourages fungal growth and deter termites and other wood-destroying insects.

This practice aligns with sustainable design principles, enhancing the durability of building materials while minimizing the necessity for chemical treatments that can be harmful to the environment. Maintaining this distance improves airflow around the wood, further reducing the likelihood of pest-related issues without relying on chemical pesticides or treatments.

The other options mentioned do not contribute to sustainable pest management practices in the same way or may even conflict with the intent of reducing chemical use and promoting ecological balance.