Rickets is a disease of which category -

Options

A. Infective disease
B. Deficiency disease
C. Communicable disease
D. Inheritable disease

Answer

### Step-by-Step Solution:

1. **Understanding Rickets**: Rickets is a disease primarily affecting children. It is characterized by the softening and weakening of bones.

2. **Cause of Rickets**: The primary cause of rickets is a deficiency of vitamin D. Vitamin D is essential for the absorption of calcium and phosphate in the body, which are crucial for healthy bone development.

3. **Sources of Vitamin D**: Vitamin D can be obtained from dietary sources such as cod liver oil, and it can also be synthesized in the skin when exposed to sunlight. The compound involved in this synthesis is dihydroxy cholecalciferol.

4. **Effects of Vitamin D Deficiency**: In children, a lack of vitamin D leads to rickets, while in adults, it can lead to a condition known as osteomalacia, which is also related to bone weakening.

5. **Classification of Rickets**: Since rickets is caused by a deficiency of a vital nutrient (vitamin D), it falls under the category of deficiency disorders.

6. **Exclusion of Other Categories**: Rickets is not an infective disease (which is caused by pathogens), nor is it an inheritable disease (which is genetic). Therefore, it is correctly classified as a deficiency disorder.

7. **Conclusion**: Based on the above analysis, rickets is categorized as a deficiency disorder.

### Final Answer:
Rickets is a deficiency disorder.

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