Which factor partly determines skin color?

Skin color is primarily determined by the amount and type of melanin produced by melanocytes in the skin, which is largely influenced by genetics. Genetics dictate the baseline levels of melanin, resulting in variations of skin color among individuals. Different ethnic backgrounds contribute to the genetic diversity seen in skin pigmentation.

While sun exposure does affect melanin production and can cause temporary changes in skin tone, it doesn't determine the inherent skin color of an individual. Similarly, blood supply can influence the appearance of the skin, particularly in terms of redness or pallor, depending on vascular conditions, but it does not define skin color itself. Age may affect skin's texture and tone over time, but it does not fundamentally alter the genetic factors responsible for skin pigmentation.

Genetics serves as the primary factor in determining skin color, making it the most pertinent choice in this context. Understanding these underlying factors enables a better grasp of dermatological and cosmetic practices.