Which of the following not a hermaphrodite animal ?

Options

A. Hirudinaria
B. Earthworm
C. Planaria
D. Nereis

Answer

To determine which of the following animals is not a hermaphrodite, we need to understand what hermaphroditism means and analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Hermaphroditism**:
- Hermaphrodite animals possess both male and female reproductive organs within the same individual. This means they can produce both eggs and sperm.

2. **Analyzing the Options**:
- **Hyrudinaria**: This is a genus of leeches that are known to be hermaphrodites. They have both male and female reproductive organs.
- **Earthworm**: Earthworms are classic examples of hermaphroditic animals. Each individual has both male and female reproductive structures.
- **Plenaria**: Planarians are flatworms that are also hermaphroditic. They contain both types of reproductive organs.
- **Neeris**: Neeris, also known as Nereis, is a genus of polychaete worms. These organisms are dioecious, meaning they have separate male and female individuals.

3. **Conclusion**:
- Among the options given, Neeris is the only one that is not a hermaphrodite. It has distinct male and female individuals, unlike the others which possess both reproductive organs.

### Final Answer:
**Neeris is not a hermaphrodite animal.**

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