Viroid was discovered by:-

Options

A. Haeckel
B. Pasteur
C. T.O. Diener
D. Theophrastus

Answer

**Step-by-Step Solution:**

1. **Understanding Viroids**: Viroids are the smallest known infectious pathogens. They are composed of circular single-stranded RNA and do not have any protein coat.

2. **Identifying the Discoverer**: The question asks who discovered viroids. The options provided are:
- A. Theckle
- B. Posture
- C. T.O. Daniel
- D. Teopratus

3. **Researching the Discovery**: The discovery of viroids is attributed to T.O. Daniel, a plant pathologist. He made this discovery in 1971 while working at an agricultural research center in Maryland.

4. **First Viroid Identified**: The first viroid identified by T.O. Daniel was the potato spindle tuber viroid, which causes disease in potatoes.

5. **Conclusion**: Based on the information gathered, the correct answer to the question "Viroid was discovered by:" is option C, T.O. Daniel.

**Final Answer**: C. T.O. Daniel

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