Chenoreceptors of the nematodes are

Options

A. Phasmids
B. Amphids
C. Plasmids
D. Statocysts

Answer

### Step-by-Step Solution:

1. **Understanding Chemoreceptors**: Chemoreceptors are specialized sensory receptors that detect chemical changes in the environment. In nematodes (roundworms), they play a crucial role in sensing various environmental factors such as temperature, salinity, and pH.

2. **Identifying Nematodes**: Nematodes are a diverse group of roundworms, and a common example is Ascaris. These organisms have specific structures that help them sense their environment.

3. **Key Structures in Nematodes**:
- **Fasmeeds**: This organ is located in the tail region of nematodes. While it is involved in modulating signals, it is not directly responsible for chemoreception.
- **Amphoedes**: This structure is found on the side of the brain in nematodes. It is specifically responsible for collecting chemoreceptor signals, making it essential for the detection of environmental changes.
- **Plasmids**: These are vectors found in bacteria and do not have a role in nematodes.
- **Stratocyst**: This organ is involved in balance and movement but is not directly related to chemoreception.

4. **Conclusion**: The primary chemoreceptors in nematodes are located in the **amphoedes**, which is responsible for collecting and processing chemoreceptive signals.

### Final Answer:
The chemoreceptors of nematodes are primarily located in the **amphoedes**.

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