The pineal gland secretes :

Options

A. Vasopressin
B. Melatonin
C. Melanin
D. MSH

Answer

**Step-by-Step Solution:**

1. **Identify the Gland**: The question asks about the hormone secreted by the pineal gland. The pineal gland is a small endocrine gland located in the brain.

2. **Review the Options**: The options provided are:
- Option 1: Vasopressin
- Option 2: Melatonin
- Option 3: Melanin
- Option 4: MSH (Melanocyte-Stimulating Hormone)

3. **Analyze Each Option**:
- **Option 1 - Vasopressin**: This hormone, also known as antidiuretic hormone (ADH), is secreted by the posterior pituitary gland, not the pineal gland. Its primary function is to regulate water balance in the body.
- **Option 2 - Melatonin**: This is the correct answer. Melatonin is a hormone produced by the pineal gland, especially during the night, and is known as the "sleep hormone" because it helps regulate sleep-wake cycles.
- **Option 3 - Melanin**: Melanin is a pigment responsible for the color of skin and hair, but it is not a hormone and is produced by melanocytes, which are stimulated by hormones from the pituitary gland.
- **Option 4 - MSH (Melanocyte-Stimulating Hormone)**: MSH is involved in the production of melanin and is secreted by the intermediate lobe of the pituitary gland, not the pineal gland.

4. **Conclusion**: After analyzing all the options, the hormone secreted by the pineal gland is **Melatonin**.

**Final Answer**: The pineal gland secretes **Melatonin**.

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