Most toxic product of vehicle pollution is:

Options

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

Answer

### Step-by-Step Solution:

1. **Understanding Vehicle Pollution**: Vehicle pollution refers to the release of harmful substances into the environment due to the operation of motor vehicles. This includes various toxic emissions that can affect air quality and human health.

2. **Identifying the Options**: The question provides four options:
- Option 1: PV (Lead)
- Option 2: CO2 (Carbon Dioxide)
- Option 3: CO (Carbon Monoxide)
- Option 4: NO2 (Nitrogen Dioxide)

3. **Analyzing Carbon Monoxide (CO)**:
- Carbon monoxide is a colorless, odorless gas produced from the incomplete combustion of fossil fuels, such as gasoline.
- It is primarily emitted by cars and trucks, which are significant sources of this pollutant.
- CO is particularly dangerous because it binds with hemoglobin in the blood, preventing oxygen transport to vital organs like the brain and heart, potentially leading to organ failure.

4. **Analyzing Other Options**:
- **Option 1: PV (Lead)**: Lead emissions from vehicles can cause lead poisoning and other health issues, but they are considered less toxic than carbon monoxide.
- **Option 2: CO2 (Carbon Dioxide)**: While CO2 contributes to global warming and is a greenhouse gas, it is not acutely toxic to humans in the same way that CO is.
- **Option 4: NO2 (Nitrogen Dioxide)**: NO2 can cause respiratory issues and contribute to acid rain, but it is also less toxic than carbon monoxide.

5. **Conclusion**: After evaluating all the options, it is clear that carbon monoxide (CO) is the most toxic product of vehicle pollution among the given choices.

### Final Answer:
The most toxic product of vehicle pollution is **Carbon Monoxide (CO)**.

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