The major part of the semen is the secretion of:

Options

A. Cowper's gland
B. Pineal gland
C. Prostate gland
D. Seminal vesicle

Answer

To solve the question regarding which gland contributes the major part of the semen, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Semen Composition**:
Semen is a fluid that contains sperm cells and various secretions from different glands in the male reproductive system. It is important to identify which gland contributes the most to this fluid.

2. **Identifying the Glands**:
The options provided are:
- Cowper's gland
- Pineal gland
- Prostate gland
- Seminal vesicle

3. **Analyzing Each Gland's Contribution**:
- **Cowper's Gland**: Also known as bulbourethral glands, they produce a small amount of pre-ejaculatory fluid.
- **Pineal Gland**: This gland is not involved in semen production; it primarily secretes melatonin.
- **Prostate Gland**: This gland contributes to the semen but is not the largest contributor.
- **Seminal Vesicle**: This gland produces a significant portion of the fluid in semen, specifically about 60% of its volume.

4. **Conclusion**:
Based on the analysis, the gland that secretes the major part of the semen is the **seminal vesicle**.

### Final Answer:
The major part of the semen is the secretion of the **seminal vesicle**.

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