Environmental pollution is the biggest problem for human being today. We all know that the environment includes the earth,water, plants and animals.If they are polluted or hurt, oour life can also be harmed. It is true that more and more trees are being cutting down. The earth is becoming warmer. If the problem continues, the world will become a desert, and people will have no place to live. The smoke produced by cars, factories and homes is polluting the air. _ gas is letting off into the air , too. The polluted air make people sick. Then there is the sound pollution. Our world is not quiet, even at night, because of the noise made by cars and people's daily life. Too much noise has a bad influence on our hearing. It has been reported that many people in a village near an airport have lost their hearing because of the noise made by planes. The water and the earth we are living on have also been polluted. The rubbish people throw away and the waste water poured by factories make the water and the soil polluted. When we drink dirty water or eat crops planted on polluted soil, we can get sick easily. Just imagine what will happen if this continues. I 'm sure it won't be a pleasant result. The best title of this passage is  _
what is the air pollution the harm of the soil pollution the environmental pollution. how to deal with the environmental pollution.