Secondary sexual characters in females

Options

A. Relaxin
B. Progesterone
C. Estrogen
D. Gonadotropin.

Answer

**Step-by-Step Solution:**

1. **Understanding Secondary Sexual Characters**:
- Secondary sexual characters are physical traits that develop during puberty, distinguishing the sexes but not directly involved in reproduction. In females, these include breast development, the onset of the menstrual cycle, and changes in voice pitch.

2. **Identifying Relevant Hormones**:
- The question provides four hormone options: relaxin, progesterone, estrogen, and gonadotropins. We need to determine which of these hormones is primarily responsible for the development of secondary sexual characteristics in females.

3. **Analyzing Each Hormone**:
- **Relaxin**: This hormone is primarily involved in childbirth and does not play a role in developing secondary sexual characteristics.
- **Progesterone**: This hormone is mainly involved in regulating the menstrual cycle and maintaining pregnancy, not in the development of secondary sexual traits.
- **Estrogen**: This hormone is crucial for the development of secondary sexual characteristics in females, such as breast development and the regulation of the menstrual cycle.
- **Gonadotropins (FSH and LH)**: These are pituitary hormones that stimulate the ovaries but do not directly cause the development of secondary sexual characteristics.

4. **Conclusion**:
- Based on the analysis, the hormone responsible for secondary sexual characteristics in females is **Estrogen**. Therefore, the correct answer is **Option 3: Estrogen**.

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