Assertion :- The hormone FSH stimulates RBCs. maturation.
Reason:- On reaching the red bone marrow FSH stimulate the maturation of RBCs

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 Text Solution:

1. **Understanding the Assertion**: The assertion states that the hormone FSH (Follicle Stimulating Hormone) stimulates the maturation of red blood cells (RBCs).

2. **Understanding the Reason**: The reason provided explains that FSH reaches the red bone marrow and stimulates the maturation of RBCs there.

3. **Analyzing FSH Function**: FSH is primarily known as a gonadotropin that plays a crucial role in the reproductive system. It stimulates the growth and maturation of ovarian follicles in females and spermatogenesis in males.

4. **Identifying the Target Cells of FSH**: FSH acts on the gonads (ovaries and testes) and does not have a direct role in the maturation of red blood cells. The receptors for FSH are located in the reproductive organs, not in the red bone marrow.

5. **Evaluating the Reason**: The reason suggests that FSH stimulates RBC maturation in the red bone marrow. However, this is incorrect as FSH does not influence RBC maturation. The maturation of RBCs is primarily regulated by erythropoietin, a hormone produced by the kidneys.

6. **Conclusion**: Since both the assertion and the reason are incorrect, the correct answer is that both the assertion and the reason are wrong.

### Final Answer:
Both the assertion and the reason are incorrect.

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