单选题：根据以下资料回答：　To keep the wheels of industry, we manufacture con

根据以下资料回答：
　To keep the wheels of industry, we manufacture consumer goods in endless quantities, and, in the process, are rapidly exhausting our resources. But this is only half the problem. What do we do with manufactured products when they are worn out? They must be disposed of, but how and where?
Unsightly junkyards full of resting automobiles already surround every city in the nation. Americans throw away 80 billion bottles and cans each year, enough to build more than ten stacks to the moon. There isn't room for much more waste, and yet the factories grind on.
　　They cannot stop because everyone wants a job. Our standard of living, one of the highest in the world, requires the consumption of manufactured products in ever-increasing amounts. Man, about to be buried in his own waste, is caught in a vicious cycle.
Only 100 years ago man lived in harmony with nature. There weren't so many people then and their wants were fewer. Whatever wastes were produced could be absorbed by nature and were soon covered over. Today this harmonious relationship is threatened by man's lack of foresight and planning, and by his carelessness and greed,for man is slowly poisoning his environment.
　　Pollution is a "dirty" word. To pollute means to contaminate--to spoil something by introducing impurities which make it unfit or uaclear to use. Pollution comes in many forms. We see it, we smell it, taste it, drink it, and stumble through it. Weqitemlly live in and breathe pollution, and, not surprisingly, it is beginning to threaten our health, our happiness, and our very civilization. Once we thought of pollution as meaning simply smog—the choking, stinging, dirty air that hovers over cities. But air pollution, while it is still the most dangerous, is only one type of contamination among several which attack the most basic life function. Through the uncontrolled use of insecticides, man has polluted the land, killing the wildlife. By dumping sewage and chemical into rivers and lakes,we have contaminated our drinking water. We are polluting the oceans, too, killing the fish and thereby depriving 　　ourselves of an invaluable food supply. Part of the problem is our exploding population.
　　More and more people produce more wastes. But this problem is intensified by our "throw-away" technology.
　　Each year American dispose of 7 million autos, 20 million tons of waste paper, 25 million pounds of toothpaste tubes and 48 million cans. We throw away gum wrappers, newspapers, and paper plates. It is no longer fashionable to reuse anything. Today almost everything is disposable. Instead of repairing a toaster or a radio, it is easier and cheaper to buy a new one and discard the old, even though 95 percem of its parts may still be functioning. Baby diapers, which used to be made of cloth and now have disposable substitutes: "Wear it once and throw it away,"will be the slogan of the fashion conscious.
　　Where is this all to end? Are we turning the world into a gigantic dump, or is there hope that we can solve the pollution problem? Fortunately, solutions are in sight. A few of them are positively ingenious. Take the problem of discarded automobiles, for instance. Each year over 40.000 of them are abandoned in New York City alone.
Eventually the discards end up in a junkyard. But cars are too bulky to ship as scrap to a steel mill. They must first be flattened. This is done in a giant compressor which can reduce a Cadillac to the size of a television set in a matter of minutes. Any leftover scrap metal is mixed with concrete and made into exceptionally strong bricks that are used in buildings and bridges. Man's ingenuity has come to his rescue.
　　What about water pollution? More and more cities are building sewage-treatment plants. Instead of being dumped into a nearby river or lake, sewage is sent through a system of underground pipes to a giant tank where the water is separated from the solid material called sludge. The sludge can be converted into fertilizer, and can also be made into bricks.
Controlling air pollution is another crucial objective. Without food, man can live about five weeks; without water, about five days. Without air, he can only live five minutes, so pure air is a must. Here the wrongdoer is the automobile. Where there is a concentration of automobiles, as in our big cities, air pollution is severe. It is important to see that our cars are equipped with pollution-control devices. Such devices effectively reduce the harmful gases emitted from the engine. Power plants, factories, and apartment buildings can also avoid air pollution. When possible they should use clean fuels like gas and oil. And the smokestacks of these buildings should be equipped with filters and other smoke-reduction devices.
Can we eliminate pollution altogether? Probably not. Modem man pollutes with everything he does, so total elimination would require drastic measures. Every power plant would have to shut down. Industries would have to close. We would have to leave all our automobiles in the garage. Every bus and truck and airplane would have to stop running. There would be no way to bring food to the cities. There would be no heat and light. Under these conditions, our population would die in a short time. Since such a drastic solution is impossible, we must employ determined public action. We can reduce pollution, even if we can't eliminate it altogether. But everyone must do
his part. We can have a clean world; we can do something. The choice is up to you.

Which of the following statement is not a cause of pollution mentioned in the passage? A．Population explosion.
B．Too much consumption.
C．It is out-dated to reuse things.
D．High unemployment rate.