Choose the correct match

Options

A. Nereis – Internal fertilisation
B. Pheretima – Internal fertilisation
C. Hirudinaria – Internal fertilisation
D. Ascaris – External fertilisation

Answer

To solve the question of matching organisms with their type of fertilization (internal or external), let's analyze each option step by step.

### Step 1: Understand the Types of Fertilization
- **Internal Fertilization**: This occurs when fertilization happens inside the female's body. The eggs mature within the body, and mating occurs physically.
- **External Fertilization**: This occurs when eggs and sperm are released into the environment, where fertilization takes place outside the body.

### Step 2: Analyze Each Option
1. **Neris**: This organism is known for external fertilization. The eggs and sperm are released into the water, making this option incorrect for internal fertilization.

2. **Ferritima (Earthworm)**: Earthworms exhibit a form of copulation where they exchange sperm externally, but fertilization occurs internally. Thus, this option is also incorrect for external fertilization.

3. **Herudinia (Leeches)**: In leeches, fertilization is internal. The eggs are produced externally, but the actual fertilization process occurs inside the body. This option is correct for internal fertilization.

4. **Ascaris**: This organism is a roundworm that undergoes internal fertilization. The fertilization happens inside the female's body, making this option incorrect for external fertilization.

### Step 3: Conclusion
Based on the analysis:
- The correct match is **Herudinia**, which is associated with internal fertilization.

### Final Answer
The correct match is **Herudinia (Leeches) - Internal Fertilization**.

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