Largest unicellular organism is

Options

A. Yeast
B. Acetabularia
C. Planaria
D. Volvox.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the largest unicellular organism among the given options: East, Acetabularia, Planaria, and Volvox.

2. **Analyzing the Options**:
- **A. East**: This seems to be a typographical error and likely refers to "yeast," which are unicellular fungi but not the largest.
- **B. Acetabularia**: This is a genus of green algae known for its large size among unicellular organisms.
- **C. Planaria**: These are flatworms and are multicellular organisms, not unicellular.
- **D. Volvox**: This is a genus of green algae that forms spherical colonies, but it is not unicellular.

3. **Identifying the Largest Unicellular Organism**: Among the options, Acetabularia is known for being a gigantic unicellular organism, making it the correct choice.

4. **Conclusion**: Based on the analysis, the largest unicellular organism from the options provided is **Acetabularia**.

**Final Answer**: The largest unicellular organism is **B. Acetabularia**.

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