A nurse is teaching a class about the function of cells in the epidermis. The nurse should include that which of the following cells determine skin color?

Choice A reason: Keratinocytes are the primary cell type found in the epidermis, comprising about 90% of the epidermal population. Their main function is the production of keratin, a fibrous protein that provides structural integrity and a waterproof barrier to the skin. They do not synthesize the pigments responsible for skin color. Choice B reason: Langerhans cells are dendritic cells that originate in the bone marrow and migrate to the stratum spinosum of the epidermis. They function as part of the immune system by acting as antigen-presenting cells. They are essential for identifying foreign pathogens but have no role in pigmentation. Choice C reason: Merkel cells are specialized epithelial cells located in the basal layer of the epidermis, where they are closely associated with sensory nerve endings. They function as mechanoreceptors for light touch. They are involved in neuroendocrine signaling and tactile sensation rather than the production of skin pigment. Choice D reason: Melanocytes are specialized cells located in the stratum basale that produce melanin, the pigment responsible for skin, hair, and eye color. Melanin is packaged into melanosomes and transferred to nearby keratinocytes. This pigment serves a vital physiological role by absorbing and scattering harmful ultraviolet radiation to protect cellular DNA.