Which of the following has not adverse effect on human health?

Options

A. NO
B. `NO_(2)`
C. `SO_(2)`
D. CO

Answer

To determine which of the following substances has not adverse effects on human health, we will analyze the effects of common air pollutants mentioned in the video transcript.

### Step 1: Identify the pollutants listed
The pollutants mentioned in the transcript are:
- Nitrogen Oxides (NOx)
- Sulfur Oxides (SOx)
- Carbon Monoxide (CO)
- Hydrogen Sulfide (H2S)
- Nitrogen Dioxide (NO2)
- Nitrate (NO3)
- Sulfur Dioxide (SO2)
- Sulfur Trioxide (SO3)
- Carbon Dioxide (CO2)

### Step 2: Analyze the effects of each pollutant
1. **Nitrogen Dioxide (NO2)**: Causes respiratory problems and shortness of breath.
2. **Nitrate (NO3)**: Associated with respiratory issues.
3. **Sulfur Oxides (SOx)**: Causes skin irritation and allergies.
4. **Carbon Monoxide (CO)**: Leads to symptoms like redness of eyes, nausea, and vomiting.
5. **Hydrogen Sulfide (H2S)**: Known for causing irritation to the eyes and respiratory system.
6. **Sulfur Dioxide (SO2)**: Causes respiratory problems and irritation.
7. **Sulfur Trioxide (SO3)**: Can lead to severe respiratory issues and is a precursor to acid rain.
8. **Carbon Dioxide (CO2)**: While it is a greenhouse gas and contributes to climate change, it does not have direct adverse effects on human health at normal atmospheric levels.

### Step 3: Identify the pollutant with no adverse effects
From the analysis, it is clear that **Carbon Dioxide (CO2)** does not have direct adverse effects on human health at normal concentrations. The other pollutants listed have known harmful effects.

### Conclusion
The correct answer to the question "Which of the following has not adverse effect on human health?" is **Carbon Dioxide (CO2)**.

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