Is `CO_(2)` a pollutant in true sense ?

Explanation

### Step-by-Step Solution:

1. **Understanding the Definition of Pollutant**:
- A pollutant is generally defined as a substance that causes harm to the environment or living organisms. It typically has adverse effects on human health or the ecosystem.

2. **Identifying CO2's Role**:
- Carbon dioxide (CO2) is a naturally occurring gas that is essential for life on Earth. It is a product of respiration in animals and plants and is used by plants for photosynthesis.

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