Which among the following is a vitamin?

The correct answer is B. Folic acid is a water-soluble vitamin that is essential for human health. It is involved in the production of red blood cells, the growth and development of the fetus, and the metabolism of proteins and nucleic acids. Folic acid deficiency can lead to anemia, birth defects, and other health problems.

Citric acid is a weak organic acid that is found in citrus fruits. It is used as a food additive, a preservative, and a flavoring agent. Glutamic acid is an amino acid that is found in proteins. It is used as a food additive, a flavoring agent, and a precursor to other chemicals.

None of these options is a vitamin.