The deficiency of vitamin D leads to

1. Analyze the question The question asks which disease results from a lack of vitamin D in the diet or body.

2. Explain the concept Vitamin D helps the body absorb calcium and phosphorus from food, and these minerals are needed to build strong bones and teeth. You get vitamin D from fish liver oil, egg yolk, and milk, and your skin also makes it when exposed to sunlight.

3. Solution: check each option

• A. Beriberi is caused by a lack of vitamin B1 (thiamine). It affects the nerves and heart. ✘
• B. Pellagra is caused by a lack of vitamin B3 (niacin). It causes dermatitis, diarrhoea, and dementia. ✘
• C. Rickets is caused by a lack of vitamin D. Bones become soft and weak, which leads to bow legs and deformed ribs in children. ✔
• D. Scurvy is caused by a lack of vitamin C. It causes bleeding gums and slow wound healing. ✘

4. Answer The correct option is C (written "ricket" in the question, but the disease is called rickets).

5. Exam tip Match each vitamin to its disease:

• D → Rickets (think "D" for "Deformed bones")
• C → Scurvy
• B1 → Beriberi
• B3 → Pellagra
• A → Night blindness
• K → Poor blood clotting

Adults can get a similar condition called osteomalacia (soft bones) from a lack of vitamin D.