Which of the following is not a vitamin of the B complex?

Carotene is not a vitamin of the B complex because it is actually a precursor to vitamin A and is classified as a provitamin. It belongs to a different category of nutrients known as carotenoids, which are pigments found in plants that can be converted into vitamin A in the body. In contrast, riboflavin, niacin, and pantothenic acid are all part of the B complex vitamins, which are essential for various metabolic processes. B vitamins are crucial for energy production, cell metabolism, and maintaining a healthy nervous system. Examples from the B complex include riboflavin (B2), which is important for energy production, niacin (B3), which helps to convert nutrients into energy, and pantothenic acid (B5), which is necessary for synthesizing coenzyme A.