Tobacco mosaic virus was the first virus discovered
by a Russian botanist in 1892. He was

Options

A. (a) Dmitrii lvanowski
B. (b) M. W. Beijerinck
C. (c) Charles Eeluse
D. (d) Adolf Mayer

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the Russian botanist who discovered the Tobacco Mosaic Virus (TMV) in 1892.

2. **Recall Relevant Information**: The Tobacco Mosaic Virus was the first virus to be discovered, and this discovery was made by a Russian botanist.

3. **Consider the Options**: The options provided include several names. We need to determine which of these names corresponds to the botanist who made the discovery.

4. **Research the Botanist**: Dmitry Ivanovsky is known for his work on the mosaic disease affecting tobacco plants. In 1892, he reported his findings regarding a disease-causing factor that could pass through a porcelain filter, indicating it was smaller than bacteria.

5. **Confirm the Discovery**: While the term "virus" was not used at the time of Ivanovsky's discovery, he was indeed the first to identify the infectious agent responsible for the mosaic disease in tobacco.

6. **Conclude the Answer**: Based on the information gathered, the correct answer to the question is Dmitry Ivanovsky.

**Final Answer**: Dmitry Ivanovsky

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