Somatostatin is produced by

Options

A. Adenohypophysis
B. Neurohypophysis
C. Pineal gland
D. Basal part of diencephalon

Explanation

### Step-by-Step Solution:

1. **Understanding Somatostatin**: Somatostatin is a hormone that plays a crucial role in regulating various physiological processes, including inhibiting the release of growth hormone.

2. **Identifying the Source**: The question asks where somatostatin is produced. It is important to know the glands involved in hormone production.

3. **Recognizing the Gland**: Somatostatin is produced by the hypothalamus, which is a gland located in the brain.

4. **Locating the Hypothalamus**: The hypothalamus is specifically located in the basal part of the diencephalon. This is a key anatomical detail that helps in identifying the correct answer.

5. **Function of Somatostatin**: Somatostatin acts as a growth hormone release inhibiting hormone. It regulates the secretion of growth hormone from the pituitary gland, particularly when there is an excess of growth hormone in the bloodstream.

6. **Conclusion**: Therefore, the correct answer to the question "Somatostatin is produced by" is the hypothalamus, which is part of the basal part of the diencephalon.

### Final Answer:
Somatostatin is produced by the hypothalamus, which is located in the basal part of the diencephalon.

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