Which of the following is a female hormone ?

Options

A. Testosterone
B. Estrogen
C. Both of these
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks to identify which of the given options is a female hormone. The options provided are testosterone, both of these, or none of these.

2. **Analyzing the Options**:
- **Testosterone**: This hormone is primarily known as the male sex hormone. It plays a crucial role in sperm production and the development of male secondary sexual characteristics, such as increased muscle mass and bone density.
- **Both of These**: This option suggests that both testosterone and another hormone (not specified) are female hormones, which is incorrect since testosterone is not a female hormone.
- **None of These**: This option implies that neither of the hormones listed is a female hormone, which is also incorrect as there is a female hormone.

3. **Identifying the Female Hormone**: The female hormone that is commonly recognized is **estrogen**. Estrogen is responsible for the development and maintenance of the female reproductive system. It plays a vital role in regulating the menstrual cycle and is essential for reproductive health.

4. **Sources of Estrogen**: Estrogen is primarily secreted by the ovaries, which are the female reproductive organs. Additionally, during pregnancy, a tissue called the placenta also secretes estrogen, facilitating the connection between the mother and the fetus.

5. **Conclusion**: Based on the analysis, the correct answer to the question "Which of the following is a female hormone?" is **estrogen**.

**Final Answer**: The female hormone is **estrogen**.

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