Vagina of the female reproductive system is

Options

A. Primary sex organ
B. Accessory sex organ
C. Secondary sex organ
D. None of the above.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the classification of the vagina within the female reproductive system. We need to determine whether it is a primary sex organ, accessory sex organ, secondary sex organ, or none of these.

2. **Defining the Terms**:
- **Primary Sex Organs**: These are the main reproductive organs necessary for reproduction. In females, this includes the ovaries, uterus, fallopian tubes, and vagina.
- **Accessory Sex Organs**: These are organs that assist in the reproductive process but are not essential for reproduction itself.
- **Secondary Sex Organs**: These are features that develop during puberty and are not directly involved in reproduction but are associated with sexual characteristics.

3. **Identifying the Role of the Vagina**: The vagina is a muscular tube that serves as the passage for menstrual fluid, receives the penis during sexual intercourse, and serves as the birth canal during childbirth. This indicates its crucial role in the reproductive process.

4. **Conclusion**: Since the vagina is essential for normal reproductive health and is classified as one of the main reproductive organs, it falls under the category of primary sex organs.

5. **Final Answer**: The vagina of the female reproductive system is a **primary sex organ**. Therefore, the correct option is **A**.

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