People who eat excess of maize in their diet suffer from -

The correct option is C Pellagra
Answer: (a)

Pellagra is a disease that occurs when a person does not get enough niacin or tryptophan. People who have maize as staple diet are prone to pellagra as maize contains poor quality protein with small quantities of lysine and tryptophan.

The most common cause of rickets is a lack of vitamin D or calcium in a child's diet.

Beriberi is a disease in which the body does not have enough thiamine (vitamin ${\text{B}}_1$).

Pernicious anemia is a type of vitamin ${\text{B}}_{12}$ deficiency anemia.