Common character between flatworms, roundworms and earthworms is -

Options

A. Parasitism
B. Acoelomate nature
C. Triploblastic
D. Pseudocoelomate

Answer

To determine the common character between flatworms, roundworms, and earthworms, we need to analyze the characteristics of each group and their respective phyla.

### Step-by-step Solution:

1. **Identify the Phyla**:
- Flatworms belong to the phylum **Platyhelminthes**.
- Roundworms belong to the phylum **Nematoda** (the transcript mistakenly refers to it as Pascalminthus).
- Earthworms belong to the phylum **Annelida**.

2. **Examine the Body Structure**:
- **Flatworms (Platyhelminthes)**: They are **acoelomate**, meaning they do not have a true body cavity (coelom).
- **Roundworms (Nematoda)**: They are **pseudocoelomate**, meaning they have a body cavity that is not fully lined with mesoderm.
- **Earthworms (Annelida)**: They are **coelomate**, meaning they have a true body cavity that is fully lined with mesoderm.

3. **Check for Common Features**:
- **Triploblastic**: All three groups (flatworms, roundworms, and earthworms) are **triploblastic**, meaning they have three germ layers: ectoderm, mesoderm, and endoderm.

4. **Conclusion**:
- The common character among flatworms, roundworms, and earthworms is that they are all **triploblastic**.

### Final Answer:
The common character between flatworms, roundworms, and earthworms is that they are **triploblastic**.

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