Laurer's canal is present in

Options

A. Ascaris
B. Taenia
C. Periplaneta
D. Fasciola

Answer

**Step-by-Step Solution:**

1. **Understanding Laurer's Canal**: Laurer's canal is a structure associated with the reproductive system in certain organisms. It is specifically found in the class Trematoda, which is a group within the phylum Platyhelminthes (flatworms).

2. **Identifying the Phylum**: The question asks where Laurer's canal is present. We need to identify the correct phylum and class that contains Laurer's canal. The phylum in question is Platyhelminthes.

3. **Classifying Trematoda**: Within the phylum Platyhelminthes, there are different classes. Laurer's canal is specifically found in the class Trematoda, which includes organisms commonly known as flukes.

4. **Evaluating the Options**: The question provides several options:
- Ascaris (Phylum Nematoda)
- Tenia (Phylum Platyhelminthes, Class Cestoda)
- Periplaneta (Phylum Arthropoda)
- Fasciola (Phylum Platyhelminthes, Class Trematoda)

5. **Analyzing Each Option**:
- **Ascaris**: This organism belongs to the phylum Nematoda and does not have Laurer's canal.
- **Tenia**: This organism is part of the class Cestoda within Platyhelminthes and does not have Laurer's canal.
- **Periplaneta**: This organism is part of the phylum Arthropoda and does not have Laurer's canal.
- **Fasciola**: This organism is part of the class Trematoda within the phylum Platyhelminthes and does have Laurer's canal.

6. **Conclusion**: Based on the analysis, the correct answer is Fasciola, as it is the only option that belongs to the class Trematoda, where Laurer's canal is present.

**Final Answer**: Laurer's canal is present in Fasciola (class Trematoda, phylum Platyhelminthes).

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