Which mineral deficiency is supplemented on a large scale in India ?

Options

A. Potassium
B. Iron
C. Iodine
D. Sodium.

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks which mineral deficiency is supplemented on a large scale in India.

2. **Consider the Options**: The options provided are potassium, iron, iodine, and sodium.

3. **Recall Common Mineral Deficiencies**: In India, several mineral deficiencies are prevalent, but we need to identify which one is specifically supplemented on a large scale.

4. **Focus on Iodine**: Iodine deficiency is a significant health issue in India. It is well-known that iodine is essential for the production of the hormone thyroxine, which is produced by the thyroid gland.

5. **Understand the Importance of Iodine**: Thyroxine is crucial for normal growth and development. A deficiency in iodine can lead to various health problems, including goiter and developmental issues.

6. **Recognize the Solution**: To combat iodine deficiency, iodized salt has been introduced widely in India. Iodized salt is regular salt (sodium chloride) that has been fortified with iodide ions.

7. **Conclude the Answer**: Based on the information, the mineral deficiency that is supplemented on a large scale in India is **iodine**.

### Final Answer:
The mineral deficiency that is supplemented on a large scale in India is **iodine**.

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