Read the following statements and choose the correct one from the following.
a ) Sulphur dioxide and carbon dioxide results in acid rain
b) Carbon dioxide is the main pollutant that is leading to global warming
c) Photochemical smog is caused by CO and aerosols

Options

A. a only correct
B. b only correct
C. c only correct
D. all are correct

Answer

To solve the question, we need to evaluate each of the three statements provided and determine which one is correct.

### Step-by-Step Solution:

1. **Evaluate Statement A**:
- Statement A claims that "Sulphur dioxide and carbon dioxide results in acid rain."
- This statement is incorrect. Acid rain is primarily caused by the presence of sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) in the atmosphere, which react with water vapor to form sulfuric and nitric acids. Carbon dioxide (CO₂) does contribute to the acidity of rainwater but is not a primary cause of acid rain.

2. **Evaluate Statement B**:
- Statement B states that "Carbon dioxide is the main pollutant that is leading to global warming."
- This statement is correct. Carbon dioxide is a significant greenhouse gas that contributes to the greenhouse effect, leading to global warming. It is released through various human activities, including burning fossil fuels and deforestation.

3. **Evaluate Statement C**:
- Statement C asserts that "Photochemical smog is caused by CO and aerosols."
- This statement is incorrect. Photochemical smog is primarily formed by the reaction of sunlight with nitrogen oxides (NOₓ) and volatile organic compounds (VOCs), not carbon monoxide (CO) and aerosols.

### Conclusion:
- Based on the evaluations:
- Statement A is incorrect.
- Statement B is correct.
- Statement C is incorrect.

Thus, the correct answer is **Statement B**.

### Final Answer:
The correct statement is **b) Carbon dioxide is the main pollutant that is leading to global warming.**

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