The first to isolate plant virus was
Or
The Tobacco mosaic virus was crystallized for first time by

Options

A. Edward Jenner
B. Louis Pasteur
C. Andre Lwoff
D. W.M. Stanley

Answer

To answer the question regarding the first to isolate the plant virus or the crystallization of the Tobacco Mosaic Virus (TMV), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Virus**: The question refers to the Tobacco Mosaic Virus (TMV), which is known as one of the first viruses to be studied and characterized.

2. **Historical Context**: TMV was first isolated in the early 20th century, and it played a significant role in the study of viruses.

3. **Crystallization of TMV**: The crystallization of TMV was a significant milestone in virology. It allowed scientists to study the virus in detail and understand its structure.

4. **Key Contributor**: The person credited with the first crystallization of TMV is Wendell M. Stanley. He achieved this in 1935, which was a groundbreaking achievement in virology.

5. **Conclusion**: Therefore, the correct answer to the question is Wendell M. Stanley.

### Final Answer:
The Tobacco Mosaic Virus was crystallized for the first time by Wendell M. Stanley.

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