Largest organism is a

Options

A. Tree
B. Fungus
C. Vine
D. Animal .

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks for the largest organism. We need to consider different categories of organisms, including plants, animals, and fungi.

2. **Consider the Largest Tree**: The tallest tree species is a Gymnosperm known as the Sequoia, commonly referred to as the Redwood tree. While it is one of the largest in height, it is not the largest organism by area.

3. **Consider the Largest Animal**: The largest animal is the blue whale, which is indeed massive. However, it is still not the largest organism when considering all forms of life.

4. **Identify the Largest Organism**: The largest known organism is a fungus called Armillaria, which can cover an area of approximately 2830 acres. This organism is found in the Malheur National Forest in Oregon.

5. **Understand the Nature of Armillaria**: Armillaria is a type of fungus that grows by feeding on the roots of trees, often leading to their decay. It acts as a decomposer in its ecosystem.

6. **Conclusion**: Based on the information gathered, the largest organism is a fungus, specifically Armillaria.

### Final Answer:
The largest organism is a fungus, specifically Armillaria.

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