Final answer:
Melanocytes are found in the epidermis, specifically in the stratum basale layer, and are responsible for producing melanin which gives the skin its color and protects it from UV radiation (option a).
Step-by-step explanation:
Melanocytes are a type of skin cell responsible for producing the pigment known as melanin, which gives color to the skin and also protects against the harmful effects of ultraviolet radiation. Melanocytes are found in the epidermis, specifically in the stratum basale, which is the bottom layer of the epidermis. Despite people having roughly the same number of melanocytes, variations in skin color are mainly due to the different amounts of melanin produced by these cells, influenced by genetics and UV exposure. The dermis, which is beneath the epidermis, contains different components such as blood vessels, sweat glands, and hair follicles, but not melanocytes.
Hence, the answer is option a.