gut paraasite belongs to

Options

A. Gestoda
B. Cestoda
C. Turbellaria
D. Both A and B

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the classification of gut parasites. We need to identify which class of organisms from the options provided are known to be gut parasites.

2. **Analyzing the Options**:
- **Option A: Gastroda** - This term does not correspond to any recognized class of flatworms or parasites. Therefore, we can rule this option out.
- **Option B: Sestoda** - This is a class within the phylum Platyhelminthes. Members of this class, such as tapeworms, are known to be gut parasites as they attach themselves to the intestinal walls of their hosts.
- **Option C: Turbellaria** - This class consists of free-living flatworms, which do not have parasitic lifestyles. Hence, this option can also be ruled out.
- **Option D: Both A and B** - Since we have already ruled out option A, this option is incorrect.

3. **Conclusion**: Based on the analysis, the correct answer is **Sestoda**, as it includes gut parasites like tapeworms.

### Final Answer:
**Sestoda**

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