The organ related with immunity is

Options

A. Liver
B. Parathyroid
C. Thymus
D. Pineal

Explanation

**Step-by-Step Solution:**

1. **Identify the Options**: The question provides four options: liver, parathyroid, thymus, and pineal gland. We need to determine which of these organs is related to immunity.

2. **Analyze the Liver**: The liver is primarily involved in detoxification and bile secretion. It does not play a significant role in the immune system. Therefore, the liver is not the correct answer.

3. **Examine the Parathyroid Gland**: The parathyroid glands are located behind the thyroid gland and are responsible for regulating calcium metabolism. They do not have a direct role in immunity. Thus, the parathyroid gland is not the correct answer.

4. **Consider the Thymus Gland**: The thymus gland is located in the chest cavity and is crucial for the development of T lymphocytes (a type of white blood cell involved in the immune response). The thymus plays a significant role in the immune system, especially in the maturation of immune cells. Therefore, the thymus gland is a strong candidate for the organ related to immunity.

5. **Review the Pineal Gland**: The pineal gland is involved in regulating circadian rhythms and secretes melatonin. It does not have a role in the immune system. Hence, the pineal gland is not the correct answer.

6. **Conclusion**: After analyzing all the options, we conclude that the organ related to immunity is the **thymus gland**.

**Final Answer**: The organ related with immunity is **thymus**.

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