**Question:** Jowar is Pellagragenic due to excess of –

**Core Concept:** Pellagra is a disease caused by deficiency of niacin (vitamin B3). Inadequate dietary intake or impaired absorption of niacin leads to the development of pellagra symptoms, which include dermatitis, dementia, and diarrhea.

**Why the Correct Answer is Right:** Pellagra is primarily caused by the deficiency of niacin (vitamin B3), which is an essential nutrient required for various cellular functions, including the production of nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). These coenzymes are involved in several biochemical reactions, particularly those involving the electron transport chain and the Krebs cycle.

**Why Each Wrong Option is Incorrect:**

A. **Option C (Copper):** Copper is a trace element that plays a role in various physiological processes, particularly in the synthesis of hemoglobin and melanin. Copper deficiency does not cause pellagra, as it is not directly involved in the production of NAD and NADP.

B. **Option D (Iron):** Iron is essential for the production of hemoglobin and myoglobin, but it does not play a direct role in the synthesis of NAD and NADP, making it unrelated to pellagra development.

C. **Option E (Vitamin B1):** Thiamine (vitamin B1) is involved in the Krebs cycle, but it is not directly responsible for the production of NAD and NADP, which is the key deficiency responsible for pellagra development.

**Clinical Pearl:** Ensuring adequate dietary intake of niacin (vitamin B3) is crucial to prevent pellagra. Jowar, a type of millet, is rich in niacin, making it a beneficial food choice for combating pellagra, especially in regions where the disease is endemic.

**Correct Answer:** Option E (Vitamin B3 or Niacin) is correct because deficiency of niacin leads to the development of pellagra. Jowar is rich in niacin, making it a beneficial food choice for combating pellagra.