The correct answer is option 1, waxes. When water comes into contact with the surfaces of bird or insect wings, it forms droplets that roll off instead of being absorbed. This is due to the presence of waxes on the wings. Waxes are hydrophobic substances that repel water, preventing it from sticking to the wing surface. Waxes are a type of lipid and are commonly found in nature, serving as a protective barrier against moisture. They are also found in other organisms like plants and help to prevent water loss. In the case of wings, the presence of waxes allows birds and insects to effectively shed water and maintain their ability to fly even in wet conditions.