Mushroom is a

Options

A. Saprophyte
B. Photosythesizer of food material
C. Facultative parasite
D. Obligate parasite.

Answer

### Step-by-Step Solution:

1. **Identify the Organism**: The question asks about mushrooms. We need to recognize that mushrooms are a type of fungus.

2. **Classify the Fungus**: Mushrooms belong to the class Basidiomycetes. This class is characterized by fungi that produce a fleshy fruiting body.

3. **Understand the Fruiting Body**: The fruiting body of mushrooms is responsible for spore production and is the part that is typically edible.

4. **Nutritional Mode**: Fungi, including mushrooms, are heterotrophic organisms. This means they cannot produce their own food and must obtain nutrients from other sources.

5. **Define Saprophyte**: A saprophyte is an organism that feeds on dead and decaying organic matter. Mushrooms obtain nutrients by growing on this type of matter.

6. **Evaluate Other Options**:
- **Photosynthesizer**: This option is incorrect because fungi do not perform photosynthesis.
- **Facultative Parasite**: This option is also incorrect as facultative parasites can switch to a parasitic mode only when necessary, while mushrooms primarily feed as saprophytes.
- **Parasite**: This is incorrect as well because mushrooms do not primarily depend on living hosts for nutrients.

7. **Conclusion**: The correct classification for mushrooms is that they are saprophytes.

### Final Answer:
Mushroom is a **saprophyte**.

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