Beginning of first menstruation is called:

Options

A. Menarch
B. Capacitation
C. Menopause
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding Menstruation**: Menstruation is a monthly cycle that occurs in females, marking the shedding of the uterine lining when pregnancy does not occur.

2. **First Menstruation**: The first occurrence of menstruation is a significant milestone in a female's life, indicating the onset of puberty and reproductive capability.

3. **Terminology**: The term used to describe the beginning of the first menstruation is "Menarche." This term is derived from the Greek word "men," meaning month, and "arche," meaning beginning.

4. **Age of Onset**: Menarche typically occurs between the ages of 13 to 15 years, coinciding with the onset of puberty.

5. **Hormonal Changes**: The onset of menarche is triggered by hormonal changes in the body, primarily the secretion of sex hormones such as estrogen and progesterone. These hormones are responsible for the development of secondary sexual characteristics and the initiation of the menstrual cycle.

6. **Conclusion**: Therefore, the correct answer to the question "Beginning of first menstruation is called:" is "Menarche."

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