Select the incorrect statement.

Options

A. Anthrax is a bacterial disease that affects humans and cattle.
B. Rust of wheat is a fungal disease that spread by air.
C. Citrus canker is a viral disease that affects citrus fruits.
D. Yellow vein mosaic is a viral disease that affects bhindi.

Explanation

To solve the question of selecting the incorrect statement, we will analyze each of the four statements provided.

### Step-by-Step Solution:

1. **Analyze Statement 1**:
- **Statement**: "Anthrax is a bacterial disease that affects human and cattle."
- **Analysis**: This statement is correct. Anthrax is indeed caused by a bacterium (Bacillus anthracis) and can affect both humans and animals, particularly cattle.

2. **Analyze Statement 2**:
- **Statement**: "Rust of wheat is a fungal disease which means causative organism is a fungus."
- **Analysis**: This statement is also correct. Rust of wheat is caused by fungi, and it spreads through spores carried by the wind.

3. **Analyze Statement 3**:
- **Statement**: "Citrus canker is a viral disease that affects citrus fruit."
- **Analysis**: This statement is incorrect. Citrus canker is caused by a bacterium (Xanthomonas citri), not a virus. Therefore, this statement is false.

4. **Analyze Statement 4**:
- **Statement**: "Yellow vein mosaic is a viral disease that affects Bhindi."
- **Analysis**: This statement is correct. Yellow vein mosaic is indeed caused by a virus and affects the okra plant (Bhindi).

### Conclusion:
After analyzing all four statements, the incorrect statement is **Statement 3**: "Citrus canker is a viral disease that affects citrus fruit."

### Final Answer:
The incorrect statement is **Statement 3**.

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