Which type of melanin is characterized by a brownish-black color?

The type of melanin that is characterized by a brownish-black color is eumelanin. Eumelanin is the most common form of melanin found in human skin and hair, and it is responsible for a wide range of colors from dark brown to black. Its higher concentration contributes to darker skin tones and black hair. This type of melanin plays an essential role in protecting the skin from UV radiation by absorbing harmful rays, thus reducing the risk of skin damage.

Pheomelanin, on the other hand, is a type of melanin that imparts a yellowish or reddish hue to hair and skin, distinguishing it from the brownish-black tones provided by eumelanin. Carotene is not a melanin but a pigment that provides a yellow-orange color, typically found in certain vegetables and signifies an overall difference in the pigment types. Lastly, hemoglobin is a protein in red blood cells responsible for transporting oxygen, and it is not a pigment associated with skin or hair color. Thus, eumelanin stands out as the correct choice when identifying the brownish-black pigment type.