Menstrual cycle is repeated at an average interval of:

Options

A. 15 days
B. 20 days
C. 28/29 days
D. One year

Answer

**Step-by-Step Solution:**

1. **Understanding the Menstrual Cycle**: The menstrual cycle refers to the regular natural changes that occur in the female reproductive system, primarily involving the ovaries and the uterus.

2. **Duration of the Cycle**: The average length of the menstrual cycle is typically between 28 to 29 days. This duration is calculated from the first day of menstruation (the start of the cycle) to the first day of the next menstruation.

3. **Phases of the Cycle**: During this period, several physiological changes occur:
- The ovaries prepare to release an egg (ovum).
- The uterus prepares its inner lining (endometrium) for potential implantation of a fertilized egg.

4. **What Happens if Fertilization Does Not Occur**: If fertilization does not take place, the endometrial lining breaks down, leading to menstruation, which is the shedding of the uterine lining along with blood and mucus.

5. **Conclusion**: Based on the information about the average duration of the menstrual cycle and the physiological changes involved, the answer to the question is that the menstrual cycle is repeated at an average interval of 28 to 29 days.

**Final Answer**: The menstrual cycle is repeated at an average interval of **28 to 29 days** (Option C).

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