Who concluded that all the vegetation is only water:

Options

A. Lavoisier
B. Aristole
C. Theophrastus
D. Van Helmont

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who concluded that all vegetation is only water.

2. **Recall Historical Context**: During the time of Van Helmont, the prevailing theory was that plants grew by consuming soil.

3. **Describe Van Helmont's Experiment**: Van Helmont conducted an experiment where he planted a seedling in a pot with a specific amount of soil (90.9 kg) and measured its initial weight (2.3 kg).

4. **Watering the Plant**: He only provided water to the plant for five years without adding any soil.

5. **Measure the Results**: After five years, he measured the weight of the plant and found that it had grown to 77 kg, while the soil's weight decreased only slightly to 90.8 kg.

6. **Conclusion**: From this experiment, Van Helmont concluded that the mass of the plant came primarily from the water it absorbed, leading him to state that all vegetation is essentially water.

7. **Identify the Correct Answer**: The correct answer to the question is Van Helmont.

**Final Answer**: Van Helmont concluded that all vegetation is only water.

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