In human the unpaired male reproductive structure is

Options

A. Testis
B. Seminal vesicle
C. Bulbourethral gland
D. Prostate

Answer

To solve the question regarding the unpaired male reproductive structure in humans, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the unpaired male reproductive structure in humans. This means we need to identify which of the given options is not found in pairs.

2. **Analyze the Options**:
- **Option A: Testes**: The testes are the male reproductive organs that produce sperm and hormones. There are two testes in males, so this option is paired.
- **Option B: Seminal Vesicles**: These glands produce seminal fluid that nourishes and helps transport sperm. There are two seminal vesicles, one on each side, making this option also paired.
- **Option C: Bulbourethral Gland**: Also known as Cowper's glands, these are responsible for producing a pre-ejaculatory fluid. There are two bulbourethral glands, one on each side, indicating this option is paired as well.
- **Option D: Prostate Gland**: The prostate gland is an accessory reproductive gland located below the urinary bladder. It is unpaired, meaning there is only one prostate gland in males.

3. **Conclusion**: After analyzing all the options, we find that the only unpaired male reproductive structure is the prostate gland.

### Final Answer:
The unpaired male reproductive structure in humans is the **prostate gland** (Option D).

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