Viroids were discovered by

Options

A. Prusiner
B. Diener
C. Pasteur
D. Felix d' Herelle

Answer

**Step-by-Step Solution:**

1. **Understanding Viroids**: Viroids are a type of pathogen that specifically cause diseases in plants. They are characterized by their genetic material, which is made up of single-stranded RNA.

2. **Characteristics of Viroids**: Viroids have circular and very small RNA, making them the smallest known pathogens. A unique feature of viroids is that they do not have a protein coat surrounding their genetic material.

3. **Identifying the Discoverer**: The question asks who discovered viroids. To answer this, we need to look at the historical context of their discovery.

4. **Reviewing Options**:
- Option 1 mentions "Prisoner," which is incorrect as it refers to prions, not viroids.
- Option 2 points to Daniel, who discovered viroids in 1971 while studying a disease in potato plants.
- Option 3 mentions Louis Pasteur, known for pasteurization, which is unrelated to viroids.
- Option 4 refers to Felix D. Hurley, who worked with bacteriophages, which are also not related to viroids.

5. **Conclusion**: Based on the information, the correct answer is that viroids were discovered by Daniel in 1971.

**Final Answer**: Viroids were discovered by Daniel in 1971.

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