Pellagra is caused due to deficiency of
a)	Niacin	b)	Pantothenic acid	c)	Tocopherol	d)	Cyanocobalamin

(a)

Pellagra is a vitamin deficiency disease most commonly caused by a chronic lack of niacin (vitamin- ) in the diet. It may also result from alternations in protein metabolism in disorders such as carcinoid syndrome.  A deficiency of the amino acid lysin can lead to a deficiency of niacin as well.