LH surge occurs during phase of menstrual cycle
(a) Menstrual phase
(b) Beginning of proliferation phase
(c) Just before end of proliferation phase
(d) At the middle of the cycle

Options

A. Menstrual phase
B. Beginning of proliferstive phase.
C. Just before end of prodiferation phase
D. At the middle of the cycle.

Answer

**Step-by-Step Solution:**

1. **Understanding the Menstrual Cycle Phases**: The menstrual cycle consists of several phases: the menstrual phase, the follicular phase (which includes the proliferative phase), ovulation, and the luteal phase. The LH (luteinizing hormone) surge is a critical event in this cycle.

2. **Identifying the LH Surge**: The LH surge is a sudden increase in luteinizing hormone levels that triggers ovulation, the release of an egg from the ovary. This surge is crucial for the timing of ovulation.

3. **Analyzing the Options**:
- **(a) Menstrual phase**: This phase involves bleeding and is not associated with an LH surge. Therefore, this option is incorrect.
- **(b) Beginning of proliferation phase**: The proliferative phase starts after menstruation, but the LH surge does not occur at this time. Hence, this option is also incorrect.
- **(c) Just before end of proliferation phase**: While the LH surge occurs towards the end of the follicular phase, it is more accurately described as occurring at the midpoint of the cycle. Thus, this option is not correct.
- **(d) At the middle of the cycle**: The LH surge occurs around the 14th day of the menstrual cycle, which is considered the middle of the cycle. This is the correct answer.

4. **Conclusion**: Based on the analysis, the correct answer is **(d) At the middle of the cycle**.

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