Assertion :- Thymus gland has important role in both CMI & AMI (Immunity).
Reason:- Thymus gland maintains BMR & growth of body.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that the thymus gland plays an important role in both Cell-Mediated Immunity (CMI) and Antibody-Mediated Immunity (AMI).
- The thymus gland produces hormones, particularly thymosins, which are crucial for the development and differentiation of T lymphocytes (T cells). T cells are essential for CMI, while B cells, which are also influenced by the thymus, are responsible for producing antibodies in AMI.

2. **Understanding the Reason:**
- The reason provided claims that the thymus gland maintains Basal Metabolic Rate (BMR) and growth of the body.
- However, this is incorrect. The thymus gland does not regulate BMR; this function is primarily associated with the thyroid gland, which produces hormones like T3 and T4 that control metabolism.

3. **Evaluating the Assertion and Reason:**
- The assertion is true because the thymus gland is indeed involved in both types of immunity.
- The reason is false because the thymus does not maintain BMR; that is the role of the thyroid gland.

4. **Conclusion:**
- Since the assertion is true and the reason is false, the correct answer is that the assertion is correct but the reason is incorrect.

**Final Answer:**
- Assertion is true; Reason is false.

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