A : The most immediate effect of FSH is the maturation of existing late primary or secondary follicle .
R : A rising level of FSH causes the developing egg within the follicle to complete the first meiotic division to form a secondary oocyte. .
(a) If both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark a
(b) If both Assertion & Reason are true but the reason is not the correct explanation of the assertion then mark b
(c) If Assertion is true statement but Reason is false then mark c
(d) If both Assertion and Reason are false statement then mark d

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion then mark (2)
C. If Assertion is true statement but Reason is false then mark (3)
D. If both Assertion and Reason are false statement then Mark (4)

Answer

To solve the question, we need to analyze both the Assertion (A) and the Reason (R) provided in the context of FSH (Follicle Stimulating Hormone) and its role in human reproduction.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "The most immediate effect of FSH is the maturation of existing late primary or secondary follicle."
- **Evaluation**: This statement is true. FSH is known to stimulate the growth and maturation of ovarian follicles.

2. **Understanding the Reason (R)**:
- The reason states that "A rising level of FSH causes the developing egg within the follicle to complete the first meiotic division to form a secondary oocyte."
- **Evaluation**: This statement is also true. FSH promotes the maturation of the follicle and leads to the completion of the first meiotic division in the oocyte, resulting in a secondary oocyte.

3. **Analyzing the Relationship**:
- We need to determine if the reason provided explains the assertion.
- Since FSH's role in follicle maturation directly relates to its effect on the oocyte completing its meiotic division, the reason does indeed explain the assertion.

4. **Conclusion**:
- Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is option (a).

### Final Answer:
(a) If both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark a.

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