Final answer:
A. Melanin is the complex protein that is responsible for determining one's skin, eye, and hair color, with its production increased by exposure to UV rays.
Step-by-step explanation:
The complex protein that determines skin, eye, and hair color is called melanin. Melanin is produced by cells known as melanocytes, which are found in the stratum basale layer of the epidermis. The melanin is then transferred to keratinocytes, the principal cells of the outer skin layer, providing pigmentation. Melanin occurs in two primary forms: eumelanin, which is black or brown, and pheomelanin, which gives a red color. People with darker skin generally produce more melanin than those with pale skin. Moreover, exposure to UV rays stimulates the production of melanin, leading to tanning and providing some protection against UV damage.
The complex protein which determines skin, eye, and hair color is called melanin. Melanin is produced by cells called melanocytes, which are found in the epidermis. It is responsible for the pigmentation of the skin, hair, and eyes. Dark-skinned individuals produce more melanin than those with pale skin.