Loss of chlorophyll of plants, premature leaf fall and yellowing of leaf is caused due to

Options

A. `CO_(2)`
B. `SO_(2)`
C. `CO`
D. `NO_(2)`

Answer

### Step-by-Step Solution:

1. **Understanding the Symptoms**: The question describes three symptoms: loss of chlorophyll, premature leaf fall, and yellowing of leaves. These symptoms indicate a problem with the plant's health, particularly related to its ability to photosynthesize.

2. **Identifying the Cause**: The symptoms mentioned are commonly associated with air pollution. Various air pollutants can affect plant health, but we need to identify which specific gas is responsible for these symptoms.

3. **Researching Air Pollutants**: Among the common air pollutants, we have:
- Carbon Dioxide (CO2)
- Sulfur Dioxide (SO2)
- Carbon Monoxide (CO)
- Nitrogen Dioxide (NO2)

4. **Analyzing the Effects of Each Gas**:
- **Carbon Dioxide (CO2)**: Essential for photosynthesis but not directly responsible for the symptoms mentioned.
- **Sulfur Dioxide (SO2)**: Known to bleach the surface of leaves and cause loss of chlorophyll, leading to yellowing of leaves and premature leaf fall.
- **Carbon Monoxide (CO)**: Generally affects respiration in animals more than plants.
- **Nitrogen Dioxide (NO2)**: Can suppress plant growth but is not primarily associated with chlorophyll loss.

5. **Conclusion**: Based on the analysis, sulfur dioxide (SO2) is the gas responsible for the loss of chlorophyll, premature leaf fall, and yellowing of leaves in plants.

### Final Answer:
The loss of chlorophyll, premature leaf fall, and yellowing of leaves in plants is caused by **sulfur dioxide (SO2)**.