Platyhelminthes are commonly called flatworms because they possess

Options

A. Dorso-ventrall flattened body
B. Laterally flattened body
C. Flame cells
D. Umbrella-shaped body

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks why Platyhelminthes are commonly referred to as flatworms.

2. **Analyzing the Options**: The options provided are:
- A) Dorsal ventral flattened body
- B) Laterally flattened body
- C) Flame cells
- D) Umbrella shaped body

3. **Identifying Characteristics of Platyhelminthes**: Platyhelminthes, or flatworms, are known for their distinct body shape. They have a flattened body structure that is characteristic of this phylum.

4. **Evaluating Each Option**:
- **Option A (Dorsal ventral flattened body)**: This option describes the body shape accurately. Flatworms are flattened from the dorsal (top) to the ventral (bottom) side.
- **Option B (Laterally flattened body)**: This is incorrect as flatworms are not primarily laterally flattened; they are dorsally flattened.
- **Option C (Flame cells)**: While flame cells are present in flatworms and are involved in excretion, they do not define why they are called flatworms.
- **Option D (Umbrella shaped body)**: This is also incorrect as flatworms do not have an umbrella-shaped body.

5. **Conclusion**: The correct answer is **Option A: Dorsal ventral flattened body**. This accurately describes the body structure of Platyhelminthes, which is the reason they are commonly called flatworms.

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