Which one can show self fertillization ?

Options

A. Earthworm
B. Liver fluke
C. Fish
D. Roundworm.

Answer

To answer the question "Which one can show self-fertilization?" we will analyze each option provided: earthworm, liver fluke, fish, and roundworm.

### Step-by-Step Solution:

1. **Earthworm**:
- Earthworms belong to the phylum Annelida.
- They possess both male and female reproductive organs (hermaphroditic).
- However, they typically engage in cross-fertilization because their reproductive organs mature at different times.
- **Conclusion**: Earthworms do not show self-fertilization.

2. **Liver Fluke**:
- Liver flukes, also known as Fasciola, belong to the phylum Platyhelminthes.
- They are hermaphroditic, meaning they have both male and female reproductive organs within a single organism.
- Liver flukes can undergo self-fertilization because they possess both types of sex organs.
- **Conclusion**: Liver flukes can show self-fertilization.

3. **Fish**:
- Fish typically have separate sexes (dioecious), meaning individual fish are either male or female.
- They do not have both male and female reproductive organs in one organism.
- **Conclusion**: Fish do not show self-fertilization.

4. **Roundworm**:
- Roundworms, also known as Ascaris, have distinct male and female individuals.
- They reproduce through cross-fertilization since males and females are separate.
- **Conclusion**: Roundworms do not show self-fertilization.

### Final Answer:
The organism that can show self-fertilization is the **Liver Fluke**.

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