How dose the pollution occur due to vehicles? give the name of vehicles causing least pollution.

How dose the pollution occur due to vehicles? give the name of vehicle

1.	How dose the pollution occur due to vehicles? give the name of vehicles causing least pollution.
Answer» The petrol and diesel spread unburn SULPHUR and nitrous ACID which MIXES and be the cause of POLLUTION. The CNG is the best fuel for avoiding the pollution . it has taken the place of petrol and diesel because it's spread more less nitrous and sulphur oxides