Flat worms are

Options

A. Dipoblastic
B. Triploblastic
C. Monoblastic
D. None of the above

Answer

### Step-by-Step Solution:

1. **Definition of Flatworms**: Flatworms belong to the phylum Platyhelminthes. They are characterized by their flat, ribbon-like bodies.

2. **Body Structure**: Flatworms have a unique body structure that is not rounded. They exhibit three primary germ layers: ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer).

3. **Triploblastic Nature**: The presence of these three layers categorizes flatworms as triploblastic organisms. This means they have a more complex body structure compared to organisms with only one or two layers (monoblastic or diploblastic).

4. **Conclusion**: Based on the characteristics and classification of flatworms, they are classified as triploblastic organisms.

### Final Answer:
Flatworms are triploblastic organisms.

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