Which of the following scientists concluded by his experiments that green plant parts play a role in purifying the noxious air only in the pressure of sunlight?

Options

A. Preistley
B. Ingenhousz
C. Sachs
D. Engelmann

Explanation

To answer the question regarding which scientist concluded that green plant parts purify the air only in the presence of sunlight, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Question**: The question asks which scientist determined that green plants purify the air only when exposed to sunlight.

2. **Review the Options**: The options provided are:
- A) Priceley
- B) Ingenhousz
- C) Satz
- D) Engelmann

3. **Recall Relevant Experiments**:
- Jan Ingenhousz conducted experiments that demonstrated the role of sunlight in the process of photosynthesis. He observed that plants produce oxygen bubbles only when they are exposed to light.
- Ingenhousz also noted that in the absence of light, plants do not produce oxygen and instead may release carbon dioxide.

4. **Conclude the Findings**: Based on Ingenhousz's experiments, it is clear that green plants purify the air (by producing oxygen) only in the presence of sunlight.

5. **Select the Correct Answer**: Therefore, the correct answer to the question is **B) Ingenhousz**.

### Final Answer:
The scientist who concluded that green plant parts purify the noxious air only in the presence of sunlight is **Jan Ingenhousz**.

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