The role of water in photosynthesis was experimentally confirmed by

Options

A. T.D.Saussure
B. Barnes
C. Liebig
D. J.R.Mayer

Explanation

To answer the question regarding the role of water in photosynthesis and who experimentally confirmed it, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photosynthesis**: Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy, using carbon dioxide and water. Oxygen is released as a byproduct.

2. **Identifying the Role of Water**: Water (H2O) is crucial in photosynthesis as it provides the electrons needed for the light-dependent reactions. During these reactions, water is split (photolysis) to release oxygen.

3. **Historical Experiments**: Several scientists contributed to our understanding of the role of water in photosynthesis. Notably:
- **Hills Reaction**: This was an early experiment that demonstrated the release of oxygen from water during photosynthesis.
- **Rubin and Kammen**: These scientists provided experimental evidence showing the involvement of oxygen derived from water in the photosynthetic process.

4. **T.D. Saussure's Contribution**: T.D. Saussure is credited with experimentally confirming the role of water in photosynthesis. He demonstrated that plants absorb water, and in the presence of sunlight, this water is broken down, leading to the release of oxygen and the uptake of carbon dioxide through stomata.

5. **Conclusion**: Based on the contributions of these scientists, T.D. Saussure is recognized for confirming the role of water in photosynthesis. Therefore, the correct answer to the question is **T.D. Saussure**.

### Final Answer:
The role of water in photosynthesis was experimentally confirmed by **T.D. Saussure**.

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