Which of these pathogens is responsible for yellow vein mosaic disease in plants?

Options

A. Bacteria
B. Amoeba
C. Fungus
D. Virus

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about the pathogen responsible for yellow vein mosaic disease in plants.

2. **Understand the Types of Pathogens**: There are several types of pathogens that can affect plants, including bacteria, fungi, viruses, and protozoa (like amoeba).

3. **Eliminate Incorrect Options**:
- **Bacteria**: The transcript states that bacteria is not the correct answer for yellow vein mosaic disease.
- **Amoeba**: Similarly, amoeba is also ruled out as a cause of this disease.
- **Fungi**: The transcript mentions that fungi do not cause yellow vein mosaic disease either.

4. **Identify the Correct Pathogen**: The transcript confirms that the correct pathogen responsible for yellow vein mosaic disease is a **virus**.

5. **Conclusion**: Therefore, the pathogen responsible for yellow vein mosaic disease in plants is a **virus**.

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