_____is synthesised by the growing ovarian follicles.

Options

A. Estrogen
B. Testosterone
C. Cortisol
D. Prolactin

Answer

**Step-by-Step Solution:**

1. **Identify the Question:** The question asks which hormone is synthesized by the growing ovarian follicles.

2. **Review the Options:** The options provided are:
- Option 1: Estrogen
- Option 2: Testosterone
- Option 3: Cortisol
- Option 4: Prolactin

3. **Understand Ovarian Follicles:** Ovarian follicles are structures within the ovaries that contain developing eggs. They play a crucial role in the female reproductive system.

4. **Determine the Function of Ovarian Follicles:** The primary function of growing ovarian follicles is to produce hormones that are essential for the regulation of the menstrual cycle and reproductive processes.

5. **Analyze Each Option:**
- **Estrogen:** This hormone is produced by the ovarian follicles and is crucial for the development of female secondary sexual characteristics and regulation of the menstrual cycle.
- **Testosterone:** This is primarily a male hormone produced in the testes, not the ovaries.
- **Cortisol:** This hormone is produced by the adrenal glands and is involved in stress response, not synthesized by ovarian follicles.
- **Prolactin:** This hormone is primarily involved in milk production and is produced in the pituitary gland, not the ovaries.

6. **Select the Correct Answer:** Based on the analysis, the hormone synthesized by the growing ovarian follicles is **Estrogen** (Option 1).

7. **Conclusion:** Therefore, the answer to the question is **Estrogen**.

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