Seatworm Enterobius is characterised by presence of

Options

A. Buccal capsule
B. Copulatory bursa
C. Cephalic alae
D. Straight tail in male

Answer

To answer the question regarding the characteristics of the seatworm Enterobius, we need to analyze the provided options and the morphology of the organism.

### Step-by-Step Solution:

1. **Identify the Organism**:
- The organism in question is Enterobius, commonly known as the pinworm or seatworm. It belongs to the phylum Nematoda (also referred to as Aschelminthes).

2. **Understanding the Options**:
- The options provided are:
1. Buccal capsule
2. Copulatory bursa
3. Cephalic alley
4. Straight tail in male

3. **Analyze Each Option**:
- **Buccal Capsule**:
- In Enterobius, the buccal capsule is absent. Therefore, this option is incorrect.
- **Copulatory Bursa**:
- The copulatory bursa is a structure found in male nematodes that aids in copulation. However, it is not a characteristic of Enterobius, as it does not possess this structure. Thus, this option is also incorrect.
- **Cephalic Alley**:
- The cephalic alley is a lateral extension found in the female Enterobius. This is a significant characteristic of the species. Therefore, this option is correct.
- **Straight Tail in Male**:
- In Enterobius, the male has a curved tail, while the female has a straight tail. Hence, this option is incorrect.

4. **Conclusion**:
- Based on the analysis, the correct answer is the presence of the **cephalic alley** in Enterobius.

### Final Answer:
Enterobius is characterized by the presence of **cephalic alley**.

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