Choose the wrong statement

Options

A. Mosaic disease in tobacco and AIDS in human being are caused by viruses
B. The viroids were discovered by D.I. Ivanowski
C. W.M. Stanley showed that viruses could be crystallized
D. The term Contagium vivum fluidum was coined by M.W. Beijerinek

Answer

To solve the question of choosing the wrong statement, let's analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "Mosaic disease in tobacco and AIDS in human beings are caused by viruses."
- **Analysis**: This statement is true. Mosaic disease in tobacco is caused by the Tobacco Mosaic Virus (TMV), and AIDS is caused by the Human Immunodeficiency Virus (HIV).

2. **Statement 2**: "The viroids were discovered by D. I. Iwanowski."
- **Analysis**: This statement is false. Viroids were actually discovered by T.O. Diener in 1971, not D. I. Iwanowski. Therefore, this is the wrong statement we are looking for.

3. **Statement 3**: "W. M. Stanley showed that viruses could be crystallized."
- **Analysis**: This statement is true. W. M. Stanley was indeed the scientist who demonstrated that viruses could be crystallized, which supports the idea that they can exist in a non-living state outside of a host.

4. **Statement 4**: "The term contagium vivum fluidum was coined by W. M. W. Beijerinck."
- **Analysis**: This statement is also true. W. M. W. Beijerinck coined the term "contagium vivum fluidum" to describe the infectious agent of tobacco mosaic disease.

### Conclusion:
The wrong statement is **Statement 2**: "The viroids were discovered by D. I. Iwanowski."

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