Rickets in children and osteomalacia in adults is caused by the deficiency of

Options

A. D
B. C
C. B
D. A

Answer

### Step-by-Step Solution:

1. **Understanding the Conditions**:
- Rickets is a condition that occurs in children, characterized by the softening and weakening of bones.
- Osteomalacia is the equivalent condition in adults, also leading to soft and weak bones.

2. **Identifying the Cause**:
- Both conditions are associated with a deficiency that affects bone health.
- The primary nutrient involved in maintaining bone density and health is Vitamin D.

3. **Role of Vitamin D**:
- Vitamin D, also known as calciferol, is crucial for the absorption of calcium and phosphorus in the body, which are essential for bone formation and maintenance.
- A deficiency in Vitamin D leads to decreased calcium absorption, resulting in weakened bones.

4. **Analyzing the Options**:
- The options provided are Vitamin D, Vitamin C, Vitamin B, and Vitamin A.
- Vitamin C is important for collagen formation, Vitamin B is involved in energy metabolism, and Vitamin A is essential for vision and immune function, but none of these directly influence bone density like Vitamin D does.

5. **Conclusion**:
- Therefore, the deficiency that causes rickets in children and osteomalacia in adults is specifically due to a lack of Vitamin D.

### Final Answer:
Rickets in children and osteomalacia in adults is caused by the deficiency of **Vitamin D** (calciferol).

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