Which one is not produced as exhaust of vehicle ?

Options

A. `SO_(2)`
B. `CO_(2)`
C. `CO`
D. flyash

Explanation

To solve the question "Which one is not produced as exhaust of a vehicle?", we can follow these steps:

### Step 1: Understand the question
The question asks us to identify which substance is not emitted from a vehicle's exhaust. The options provided are SO2 (sulfur dioxide), CO2 (carbon dioxide), CO (carbon monoxide), and fly ash.

### Step 2: Analyze the options
- **SO2 (Sulfur Dioxide)**: This gas is produced from the combustion of fossil fuels, especially those containing sulfur, and is commonly found in vehicle exhaust.
- **CO2 (Carbon Dioxide)**: This is a major product of combustion in vehicles, resulting from the burning of carbon-based fuels.
- **CO (Carbon Monoxide)**: This is a toxic gas produced during incomplete combustion of carbon-containing fuels in vehicles.
- **Fly Ash**: This is a byproduct of burning coal in power plants and is not produced by vehicle exhaust.

### Step 3: Identify the correct answer
From the analysis, we can see that SO2, CO2, and CO are all produced as exhaust gases from vehicles. However, fly ash is not produced during the combustion process in vehicles. Therefore, the correct answer is **fly ash**.

### Final Answer:
The substance that is not produced as exhaust of a vehicle is **fly ash**.

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