Photosynthesis (nourishment in light) was discovered by

Options

A. Stephen Hales
B. Priestley
C. Ingenhousz
D. Van Mayer.

Answer

**Step-by-Step Solution:**

1. **Understanding Photosynthesis**: Photosynthesis is the process by which green plants convert light energy into chemical energy to produce their own food. This process primarily involves the use of carbon dioxide, water, chlorophyll, and sunlight.

2. **Evaluating the Options**:
- **Stephen Hales**: He demonstrated that green plants require sunlight for nutrition but did not discover the process of photosynthesis.
- **Joseph Priestley**: He is known for his bell jar experiment, which showed that plants can purify air and produce oxygen, but he did not discover photosynthesis as a process.
- **Jan Ingenhousz**: He conducted experiments with the aquatic plant Hydrilla and discovered that in the presence of sunlight, small bubbles of oxygen are released from the green parts of the plant. This was a significant finding that contributed to the understanding of photosynthesis.
- **Van Meyer**: He proposed that green plants transform light energy into chemical energy but did not specifically discover photosynthesis.

3. **Identifying the Correct Answer**: Among the options, Jan Ingenhousz is the one who discovered that sunlight is essential for the process of photosynthesis, as he demonstrated that oxygen is produced by plants in sunlight.

4. **Conclusion**: Therefore, the correct answer to the question "Photosynthesis (nourishment in light) was discovered by" is **Jan Ingenhousz**.

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