This one plays an important role in immune system

Options

A. Pineal gland
B. thyroid
C. parathyroid
D. Thymus gland

Answer

**Step-by-Step Solution:**

1. **Identify the Gland in Question**: The question asks about a gland that plays an important role in the immune system.

2. **Recognize the Thymus Gland**: The gland that is specifically known for its role in the immune system is the thymus gland.

3. **Understand the Function of the Thymus Gland**: The thymus gland is primarily responsible for the maturation of T-lymphocytes (T-cells), which are crucial for the adaptive immune response.

4. **Note the Active Period**: The thymus gland is most active during childhood and puberty. After puberty, it begins to shrink and is gradually replaced by fatty tissue.

5. **Role in Autoimmunity**: The thymus gland helps the body to distinguish between self and non-self, thus preventing autoimmunity, where the immune system mistakenly attacks the body’s own cells.

6. **Conclusion**: Therefore, the gland that plays an important role in the immune system is the thymus gland.

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