Which part of the skin houses the hair follicles?

The dermis is the correct answer as it is the deeper layer of skin that houses the hair follicles. This layer consists of connective tissue that supports the skin’s structure and contains essential components such as blood vessels, nerves, and hair follicles. Hair follicles are embedded in the dermal layer, surrounded by a layer of epidermis at the surface, and are responsible for hair growth.

The epidermis, while it plays a crucial role in protecting the body and forming a barrier, does not contain hair follicles itself; it is primarily composed of layers of cells that do not extend deeply enough to house these structures. Keratin, on the other hand, is a protein that is a major component of hair and the outer layer of skin but does not specifically refer to any layer of skin housing hair follicles. The term "caudal" relates to the position of an organism and does not pertain to the skin structure or the location of hair follicles.

Understanding the dermis and its role in supporting hair follicles is essential in livestock selection and evaluation, as the health and condition of the skin and coat can be indicative of the overall well-being of the animal.