Answer: Harmful gases and smoke
Step-by-step explanation:
The harmful gases that cause air pollution are released from the vehicles and caused air pollution. This is very harmful for the plants, animals and human beings.
These gases are released from the automobiles, factories and cause pollution into the environment which can cause respiratory disorders.
The smoke is also a pollutant which is released by burning of the fossil fuels into the environment.
The air pollution can be reduced by using catalytic converters in the vehicles, by filtering the harmful gases before releasing it into the environment.