which is the inhibitory hormone of GH

Options

A. Insulin
B. Somatostatin
C. Parathormone
D. Testosterone.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the inhibitory hormone of growth hormone (GH). Growth hormone is produced by the anterior pituitary gland and plays a crucial role in growth, metabolism, and body composition.

2. **Identifying the Options**: The options provided are:
- A) Insulin
- B) Somatostatin
- C) Parathormone
- D) Testosterone

3. **Evaluating Each Option**:
- **A) Insulin**: This hormone is secreted by the beta cells of the pancreas and is primarily involved in regulating blood glucose levels. It does not inhibit growth hormone, so this option is incorrect.
- **B) Somatostatin**: This is the correct answer. Somatostatin is known to inhibit the release of growth hormone from the anterior pituitary gland. It is also secreted by the gamma cells of the pancreas and has roles in inhibiting insulin and glucagon release.
- **C) Parathormone**: This hormone is secreted by the parathyroid glands and is involved in regulating calcium levels in the blood. It does not have a direct role in inhibiting growth hormone, making this option incorrect.
- **D) Testosterone**: This is a male sex hormone responsible for the development of male secondary sexual characteristics. It does not inhibit growth hormone, so this option is also incorrect.

4. **Conclusion**: Based on the evaluation, the inhibitory hormone of growth hormone is **Somatostatin** (Option B).

**Final Answer**: Somatostatin

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