Answer is : (b) Nicotine
Pellagra cannot be cured by nicotine. Instead, pellagra can be cured by giving niacine, nicotinamide and tryptophan. Pellagra is a disease caused by a lack of the vitamin niacin (vitaminB3) which includes both nicotinic acid and nicotinamide and its precursors, i.e. the amino acid tryptophan. The main symptoms of pellagra are dermatitis, dementia and diarrhoea.
