Which of the following structures are considered appendages of the skin?

The correct answer is that both hair and nails are considered appendages of the skin. These structures arise from the epidermis and have specialized functions that contribute to the overall health and protection of the skin. Hair helps to provide insulation and can also serve as a sensory function, as it is rooted in nerve endings that can detect changes in the environment. Nails, on the other hand, provide protection for the tips of the fingers and toes, as well as enhance the ability to perform tasks requiring dexterity, like picking up small objects.

Both hair and nails grow from their respective follicles and are made primarily of a protein called keratin, which is also a fundamental component of the skin itself. By understanding that both hair and nails play critical roles in protection, sensation, and functionality, it becomes clear that they are integral appendages of the skin's structure.