What do materials commonly found in buildings provide for fungal growth?

Materials commonly found in buildings, such as wood, drywall, and other organic substances, provide essential nutrients that support fungal growth. Fungi thrive in environments that offer a food source, and organic materials are rich in carbohydrates and proteins that serve as conducive substrates for mold and mildew. The decomposition process of these materials further enhances the nutrient availability for fungi.

While water and air are also critical for fungal proliferation, the focus of the question specifically emphasizes the role of building materials in terms of providing a food source—thus, the correct choice highlights that it is the nutrients within these materials that directly facilitate the growth of fungi.