When air is contaminated by unwant substances which have a harmful effoon both the living and the non-living the are called :

Options

A. Water pollution
B. Air pollution
C. Land pollution
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the term used to describe air that is contaminated by unwanted substances which have harmful effects on both living and non-living things.

2. **Identifying Key Terms**:
- Contaminated air
- Unwanted substances
- Harmful effects
- Living and non-living things

3. **Defining Contaminated Air**: When air is mixed with unwanted substances, it becomes impure. These unwanted substances can be gases, particulate matter, or other pollutants that degrade air quality.

4. **Recognizing the Effects**: The presence of these harmful substances in the air can lead to health problems for living organisms (like humans and animals) and can also cause damage to non-living things (like buildings and the environment).

5. **Conclusion**: The term that describes air contaminated by harmful substances is called "air pollution."

6. **Final Answer**: The correct answer is "air pollution."

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