Largest acellular, green,marine alga ,popularly called umbrella plant is

Options

A. Ulva
B. Acetabularia
C. Spirogyra
D. Volvox

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the largest acellular green marine alga that is popularly known as the umbrella plant.

2. **Analyze the Options**: The options provided are:
- Option 1: Ulva
- Option 2: Acetabularia
- Option 3: Spirogyra
- Option 4: Walbox

3. **Recall Characteristics of Each Option**:
- **Ulva**: Known as sea lettuce, it is a multicellular green alga but not referred to as the umbrella plant.
- **Acetabularia**: This is a unicellular green alga that can grow quite large (up to 10 cm) and has an umbrella-like structure at its top, which is why it is called the umbrella plant.
- **Spirogyra**: This is a filamentous green alga and does not have an umbrella shape.
- **Walbox**: This is not a commonly known alga and is not referred to as the umbrella plant.

4. **Determine the Correct Answer**: Based on the characteristics and the unique structure of Acetabularia, it is clear that this is the largest acellular green marine alga that is popularly called the umbrella plant.

5. **Conclusion**: The correct answer is **Option 2: Acetabularia**.

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