Testosterone is secreted by

Options

A. Acinar cells
B. graafian follicles
C. Leyding cells
D. Hepatic cells.

Answer

**Step-by-Step Solution:**

1. **Understanding the Hormone**: Testosterone is known as the male sex hormone and is classified under androgens. It plays a crucial role in male reproductive development and functions.

2. **Source of Testosterone**: Testosterone is primarily secreted from the testes, which are the male reproductive organs.

3. **Identifying the Cells**: Within the testes, testosterone is specifically produced by Leydig cells. These cells are located in the interstitial spaces between the seminiferous tubules in the testes.

4. **Role of Other Hormones**: The secretion of testosterone is stimulated by luteinizing hormone (LH), which is released from the pituitary gland. This hormone triggers the Leydig cells to produce testosterone.

5. **Eliminating Incorrect Options**:
- **A. Acinar cells**: These are found in the pancreas and are not involved in testosterone production.
- **B. Graafian follicles**: These are structures in the ovaries of females and are responsible for producing estrogen, not testosterone.
- **D. Hepatic cells**: These are liver cells and do not secrete testosterone.

6. **Conclusion**: Based on the information above, the correct answer to the question "Testosterone is secreted by" is option C: Leydig cells.

**Final Answer**: C. Leydig cells

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