The organs involved in the reproductive system can be grouped as primary and secondary. Which of the following is not a secondary sex organ ?
(1) Prostate gland
(2) Mammary gland
(3) Seminal vesicle
(4) Ovary

Options

A. Only (2)
B. Both (2) & (4)
C. Only (4)
D. (1) , (2) & (3)

Answer

To solve the question regarding which of the following is not a secondary sex organ, we will analyze each option provided:

1. **Prostate gland**:
- The prostate gland is considered a secondary sex organ. It plays a crucial role in the male reproductive system by producing a fluid that nourishes and transports sperm.

2. **Mammary gland**:
- Mammary glands are also classified as secondary sex organs. They are responsible for milk production in females and play a role in nurturing offspring.

3. **Seminal vesicle**:
- Seminal vesicles are another example of secondary sex organs. They contribute to the formation of semen by producing a significant portion of the fluid that carries sperm.

4. **Ovary**:
- Ovaries are classified as primary reproductive organs. They are responsible for producing eggs (ova) and hormones such as estrogen and progesterone.

Now, based on this analysis, we can conclude that the organ that is **not a secondary sex organ** is the **ovary**.

**Final Answer**: (4) Ovary