In which duration menstrual cycle both LH and FSH attain a peak level:

Options

A. (a) `14^(th)` Day
B. (b) `7^(th)` Day
C. (c) `21^(st)` Day
D. (d) `9^(th)` Day

Answer

To determine the duration of the menstrual cycle during which both LH (luteinizing hormone) and FSH (follicle-stimulating hormone) attain peak levels, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Menstrual Cycle**: The menstrual cycle typically lasts about 28 days, but it can vary. It consists of several phases: the follicular phase, ovulation, and the luteal phase.

2. **Identify Key Hormones**: LH and FSH are crucial hormones in the menstrual cycle. FSH is responsible for stimulating the growth of ovarian follicles, while LH triggers ovulation.

3. **Locate the Ovulation Phase**: Ovulation generally occurs around the midpoint of the menstrual cycle. In a typical 28-day cycle, this is approximately on the 14th day.

4. **Hormonal Surge**: Both LH and FSH experience a surge just before ovulation. This surge is critical for the release of the ovum (egg) from the ovary.

5. **Peak Levels**: Research indicates that the peak levels of both LH and FSH occur around the 12th to 14th day of the cycle. However, the most significant surge of LH, known as the LH surge, occurs specifically on the 14th day.

6. **Conclusion**: Therefore, the correct answer to the question is that both LH and FSH attain peak levels on the **14th day** of the menstrual cycle.

### Final Answer:
**Option A: 14th day**

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