单项选择题
A．it's bad for all living things in the world B．it makes much noise C．it makes our rivers and lakes dirty D．it makes us angry more easily
A．water pollution B．air pollution C．noise pollution D．rubbish
A．because the earth is being polluted day and night B．thanks to science development C．because of the rise in population D．because the earth is blown away by the wind every years