Theory of Abiogenesis was believed by

Options

A. Aristotle
B. Thales and Plato
C. Von Helmont
D. All these

Answer

**Step-by-Step Solution:**

1. **Understanding Abiogenesis**: The theory of abiogenesis suggests that life originated from non-living matter through spontaneous processes. This means that living organisms could arise from inorganic substances without the need for pre-existing life.

2. **Identifying Key Figures**: The question asks who believed in the theory of abiogenesis. We need to identify the philosophers and scientists associated with this theory.

3. **Analyzing the Options**:
- **Option A: Aristotle** - A prominent Greek philosopher who proposed ideas about the spontaneous generation of life.
- **Option B: Thales** - Another Greek philosopher, but less directly associated with abiogenesis.
- **Option C: von Helmont** - A scientist who conducted experiments and believed that life could arise from non-living materials, specifically citing human sweat and wheat grains.
- **Option D: All of these** - This option suggests that all the mentioned figures believed in abiogenesis.

4. **Evaluating the Correct Answer**: While Aristotle and von Helmont are associated with the theory of abiogenesis, Thales is not directly linked to this theory. Therefore, the most accurate answer is option C, which specifically identifies von Helmont as a proponent of the theory.

5. **Final Conclusion**: The correct answer to the question is **option C: von Helmont**.

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