Answer:
d) Fur
Explanation:
Their skin is covered in a thick layer of hair known as fur.
Protection, sensing, waterproofing, and camouflaging are just a few of the many purposes served by mammalian fur. But thermoregulation is the most critical.
Modern animals use their hair to insulate, hide, signal, defend, and sense their immediate surroundings, all of which is accomplished via the use of hair. A camel's ability to survive in the desert during the day is a good example of the benefits of insulation.
