Air pollution affects:

Options

A. Leaves
B. roots
C. Stem
D. Flowers.

Answer

**Step-by-Step Solution:**

1. **Understanding Air Pollution**: Air pollution refers to any undesirable change in the air that decreases its quality. It can be caused by various pollutants, including particulate matter, gases, and chemicals.

2. **Identifying the Effects on Plants**: The question asks about the effects of air pollution on specific parts of plants: leaves, roots, stems, and flowers.

3. **Effect on Leaves**:
- Leaves are directly affected by air pollution. They have stomata, which are small openings that allow for the exchange of gases (O2 and CO2).
- Air pollutants, such as particulate matter, can settle on the leaf surface, which can block these stomata and hinder gas exchange.
- Additionally, certain pollutants like sulfur dioxide can damage chlorophyll, the pigment responsible for photosynthesis, further impacting the plant's health.

4. **Effect on Roots, Stems, and Flowers**:
- While air pollution primarily affects leaves, it can also have indirect effects on roots and other parts of the plant. However, the most immediate and direct impact is on the leaves.
- The roots and stems are not as directly impacted by air pollution as the leaves are, making the first option the most accurate.

5. **Conclusion**: Based on the analysis, the correct answer is that air pollution affects the leaves of plants directly.

**Final Answer**: Air pollution affects leaves.

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