Which of the following events is correctly matched with the time period in a normal menstrual cycle?

Options

A. Release of egg - `5"th"` day
B. Endometrium regenerates - `5 - 10` days
C. Rise in progesterone level - `4 - 15` days
D. Endometrium secretes nutrients for implantation - `11 - 18` days

Answer

To determine which event is correctly matched with the time period in a normal menstrual cycle, we need to analyze each option based on our understanding of the menstrual cycle phases and the associated hormonal changes.

### Step-by-Step Solution:

1. **Understanding the Menstrual Cycle**:
- The normal menstrual cycle lasts about 28 days and is divided into four main phases: menstrual phase (bleeding), proliferative phase, ovulatory phase, and secretory (luteal) phase.

2. **Analyzing Each Option**:
- **Option 1: Release of egg on the 5th day**:
- This is incorrect. Ovulation typically occurs around the 14th day of the cycle, not the 5th.

- **Option 2: Endometrium regeneration from 5 to 10 days**:
- This is correct. After menstruation (which lasts about 4-5 days), the endometrium begins to regenerate during the proliferative phase, which spans approximately from day 6 to day 13.

- **Option 3: Rise in progesterone level from 4 to 15 days**:
- This is incorrect. Progesterone levels rise after ovulation, primarily during the secretory phase, which occurs from about day 15 to day 23.

- **Option 4: Endometrium secretes nutrients for implantation from 11 to 18 days**:
- This is incorrect. The endometrium prepares for potential implantation during the secretory phase, which is primarily from day 15 to day 23, when progesterone is at its peak.

3. **Conclusion**:
- The only correct match is **Option 2**: Endometrium regeneration occurs from 5 to 10 days.

### Final Answer:
**Option 2: Endometrium regeneration from 5 to 10 days is the correct match.**

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