Which one is a primary sex organ ?

Options

A. Scrotum
B. Penis
C. Testis
D. Prostate.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the identification of a primary sex organ among the given options: scrotum, penis, testes, and prostate.

2. **Defining Primary Sex Organs**: Primary sex organs are the organs that are directly involved in the production of gametes (sperms in males and eggs in females) and the secretion of sex hormones.

3. **Analyzing the Options**:
- **A. Scrotum**: The scrotum is a pouch that holds the testes and helps regulate their temperature. It does not produce gametes or hormones.
- **B. Penis**: The penis is involved in the delivery of sperm but does not produce sperm or hormones.
- **C. Testes**: The testes are the male reproductive organs that produce sperm and secrete testosterone, making them the primary sex organs in males.
- **D. Prostate**: The prostate gland contributes to semen production but is not involved in gamete production.

4. **Conclusion**: Based on the definitions and functions of the organs, the primary sex organ in males is the testes, as they are responsible for producing sperm and male sex hormones.

5. **Final Answer**: The correct answer is **C. Testes**.

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