Black stem rust of Wheat is caused by

Options

A. Fungus
B. Protozoan
C. Alga
D. Bacterium

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about the cause of "black stem rust of wheat".

2. **Understand the Options**: The options provided are:
- Option 1: Fungus
- Option 2: Protozoan
- Option 3: Algae
- Option 4: Bacterium

3. **Research the Causative Agent**: The disease black stem rust of wheat is known to be caused by a specific organism.

4. **Identify the Organism**: The organism responsible for black stem rust is *Puccinia graminis*.

5. **Classify the Organism**: *Puccinia graminis* is classified as a fungus.

6. **Conclusion**: Since the causative agent of black stem rust is a fungus, the correct answer is option 1: Fungus.

**Final Answer**: Black stem rust of wheat is caused by a fungus.

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