Dwarfism occurs when there is
(i) Over secretion of growth hormone
(ii) Under secretion of growth hormone
(iii) Over secretion of somatostatin
(iv) Under secretion of somatostatin

Options

A. (i) and (iii)
B. Only (ii)
C. (ii) and (iii)
D. (ii) and (iv)

Answer

To determine the cause of dwarfism from the given options, we need to analyze each option in relation to the role of growth hormone and somatostatin in the body.

### Step-by-Step Solution:

1. **Understanding Dwarfism**: Dwarfism is characterized by significantly shorter stature than average, often due to hormonal imbalances during childhood.

2. **Role of Growth Hormone (GH)**: Growth hormone is produced by the anterior pituitary gland and is crucial for growth and development, particularly in bones and muscles.

3. **Identifying the Cause of Dwarfism**:
- **Option (i)**: Over secretion of growth hormone - This would lead to excessive growth, not dwarfism.
- **Option (ii)**: Under secretion of growth hormone - This directly correlates with pituitary dwarfism, as insufficient GH leads to stunted growth.
- **Option (iii)**: Over secretion of somatostatin - Somatostatin inhibits the release of growth hormone. Excess somatostatin can lead to reduced levels of GH, which can also contribute to dwarfism.
- **Option (iv)**: Under secretion of somatostatin - This would not cause dwarfism; instead, it could lead to increased growth hormone levels.

4. **Conclusion**: The correct answers are (ii) Under secretion of growth hormone and (iii) Over secretion of somatostatin, as both conditions can lead to dwarfism.

### Final Answer:
The correct options are (ii) Under secretion of growth hormone and (iii) Over secretion of somatostatin.

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