Who concluded that all the vegetation is only water:

Options

A. Option1 Lavoisier
B. Option2 Aristotle
C. Option3 Theophrastus
D. Option3 Van Helmont

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who concluded that all vegetation is derived solely from water. This is a historical inquiry into the contributions of various philosophers and scientists in the field of plant nutrition.

2. **Analyzing the Options**: The options provided are:
- Lavieuser
- Aristotle
- Theophrastus
- Van Helmont

3. **Researching Each Option**:
- **Lavieuser**: Known for his experiments with phosphorus and sulfur, he concluded that these elements gain weight by combining with air, but he did not focus on water as the source of plant mass.
- **Aristotle**: A great philosopher who made significant contributions across various fields, but he did not specifically conclude that plants are made of water.
- **Theophrastus**: A philosopher who expanded on Aristotle's work but did not specifically address the source of plant mass as water.
- **Van Helmont**: Conducted an experiment where he planted a willow tree and only watered it for five years. He observed that the tree gained a significant amount of weight while the soil lost very little, leading him to conclude that the mass of the plant came primarily from water.

4. **Concluding the Answer**: Based on the analysis, Van Helmont is the correct answer as he is the one who concluded that all vegetation is derived from water.

5. **Final Answer**: The correct answer is **Van Helmont**.

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