Assertion : Menarche starts around the age of puberty .
Reason : After birth oocyte is matured and developed to form Graafian follicle .

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion .
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False .
D. If both Assertion & Reason are False.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Menarche starts around the age of puberty." Menarche is the first occurrence of menstruation, which typically happens during puberty, marking the onset of a female's reproductive capability. This statement is true.

2. **Understanding the Reason**:
- The reason provided is "After birth, oocyte is matured and developed to form Graafian follicle." To analyze this, we need to understand the process of oogenesis. Oogenesis begins in the female fetus, where oogonia develop into primary oocytes, but these primary oocytes are arrested in prophase I of meiosis until puberty. Therefore, the statement that oocytes mature after birth is incorrect. Oocytes do not mature until puberty when they resume meiosis and develop into Graafian follicles.

3. **Evaluating the Relationship**:
- The assertion is true, but the reason is false. The reason does not correctly explain the assertion because the maturation of oocytes occurs after puberty, not after birth.

4. **Conclusion**:
- Based on the analysis, the correct answer is that the assertion is true, and the reason is false.

### Final Answer:
- Assertion is true, Reason is false.