Extract of Tobacco with Mosaic disease was called contagium vivum fluid by

Options

A. Mayer
B. Ivanowski
C. Bejjerink
D. Pasteur.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the individual who referred to the extract of tobacco infected with mosaic disease as "contagium vivum fluid."

2. **Identifying the Disease**: The disease in question is the Tobacco Mosaic Disease, which affects tobacco plants and is caused by the Tobacco Mosaic Virus (TMV).

3. **Historical Context**: The term "contagium vivum fluid" translates to "living contagious fluid," which was used to describe the infectious agent responsible for the disease.

4. **Key Figure**: The scientist who coined this term is Martinus Beijerinck. He was a Dutch microbiologist who conducted significant research on viruses.

5. **Beijerinck’s Contribution**: In his studies, Beijerinck demonstrated that the infectious agent could pass through filters that would normally retain bacteria, indicating that it was a new type of infectious agent, which we now know as a virus.

6. **Conclusion**: Therefore, the correct answer to the question is Martinus Beijerinck.

**Final Answer**: Martinus Beijerinck.

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