Planting more and more trees helps to :

Options

A. Reduce `CO_(2)` in the air
B. increase `CO_(2)` in the air
C. reduce `O_(2)` in the air
D. reduce `CO_(2)` and increase `O_(2)` in the air

Answer

To solve the question "Planting more and more trees helps to:", we will analyze the effects of trees on carbon dioxide (CO2) and oxygen (O2) levels in the atmosphere through the process of photosynthesis.

### Step-by-Step Solution:

1. **Understanding Photosynthesis**:
- Photosynthesis is the process by which green plants, including trees, convert carbon dioxide and water into glucose and oxygen using sunlight.
- The general equation for photosynthesis can be represented as:
\[ 6CO_2 + 6H_2O \xrightarrow{sunlight} C_6H_{12}O_6 + 6O_2 \]
- In this equation, 6 molecules of carbon dioxide and 6 molecules of water produce 1 molecule of glucose and 6 molecules of oxygen.

2. **Analyzing the Inputs and Outputs**:
- During photosynthesis, trees absorb CO2 from the atmosphere.
- They utilize this CO2 along with water to produce glucose (which is used for energy and growth) and release O2 back into the atmosphere.

3. **Effects on Atmospheric Gases**:
- Since trees absorb CO2, they help to **reduce** the concentration of carbon dioxide in the air.
- Simultaneously, by releasing O2, they help to **increase** the concentration of oxygen in the air.

4. **Conclusion**:
- Based on the process of photosynthesis, we can conclude that planting more trees helps to **reduce CO2 and increase O2** in the air.

### Final Answer:
Planting more and more trees helps to **reduce CO2 and increase O2 in the air.** (Option D)

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