Which of the following is NOT a function of the dermis?

In the context of the functions of the dermis, the correct choice is D, as the dermis does not produce nails. Nails are produced by the nail matrix, which is located at the base of the nail under the cuticle and is part of the epidermis rather than the dermis.

The dermis primarily serves several key roles that are crucial for skin health and functionality. It provides structural support due to its dense connective tissue, which contains collagen and elastin fibers, helping maintain skin elasticity and firmness. The dermis also contains various components, such as blood vessels and nerves, contributing to the skin's ability to regulate temperature and sense external stimuli.

While the dermis does assist in protecting the body by acting as a barrier to environmental factors, it does not store fat, as that function is primarily associated with the subcutaneous layer (hypodermis) beneath the dermis. Therefore, understanding the specific roles of each skin layer helps clarify why producing nails is not attributed to the dermis.