Question

What is the least polluting fuel for vehicles?

• A. Petrol
• B. Diesel
• C. Compressed Natural Gas (CNG)
• D. None of these

Hint:

Remember the hierarchy of common fuels from most to least polluting: Diesel>Petrol>CNG. Electric vehicles would be even cleaner at the point of use.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
The question asks to identify the vehicular fuel that produces the fewest harmful emissions when burned, compared to the other options.

Step 2: Detailed Explanation:
- Petrol and Diesel are liquid fossil fuels that, upon combustion, release significant amounts of pollutants like carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons, and particulate matter (PM), especially diesel.
- Compressed Natural Gas (CNG) is primarily methane (CH4). It burns much more cleanly than petrol or diesel. It produces significantly lower amounts of PM, CO, and hydrocarbons. While it does produce NOx, overall emissions are considerably less harmful.
- For this reason, CNG is promoted as a cleaner alternative fuel for vehicles in many cities to combat air pollution.

Step 3: Final Answer:
Compared to petrol and diesel, Compressed Natural Gas (CNG) is the least polluting fuel.