Incomplete alimentary cannal occurs in

Options

A. Fasciola
B. Ascaris
C. Wuchereria
D. Rhabditis

Answer

### Step-by-Step Solution:

1. **Understanding the Alimentary Canal**: The alimentary canal refers to the complete digestive tract that includes the mouth, esophagus, stomach, intestines, and anus. An incomplete alimentary canal lacks one or more of these components.

2. **Identifying Organisms with Incomplete Alimentary Canals**: In the context of flatworms (Platyhelminthes), many of them exhibit an incomplete alimentary canal. This means they have a mouth and digestive cavity but do not have a separate anus.

3. **Example of an Organism**: One specific example of a flatworm with an incomplete alimentary canal is the liver fluke, scientifically known as *Fasciola hepatica*. This organism has a mouth that leads to a digestive cavity but does not have an anus.

4. **Functionality of Incomplete Alimentary Canals**: In organisms with an incomplete alimentary canal, digestion occurs extracellularly, meaning that food is broken down outside of the cells and absorbed into the body. The waste is expelled through the same opening (the mouth) that food enters.

5. **Conclusion**: Therefore, the incomplete alimentary canal occurs in organisms such as *Fasciola hepatica*, which is a type of flatworm.