Read the passage, and choose the correct answer A, B, C or D for each question.

Saving the Environment: One Home at a Time

Pollution can be seen not only throughout the world, but also in our own homes. It comes from household chemicals, the amount of water people use and the waste people produce and throw away. What can be done to stop this pollution? Surprisingly, a person can help save the environment by doing simple things.

First, we need to recycle, which allows products to be used over and over again. Recycling can also reduce the number of trees cut down to produce paper products. It takes very little effort. It is not hard to place plastic and glass bottles, aluminum cans and paper in a bin. Anyone can do it.

Second, we need to watch the amount of water used in the home. It can be conserved by taking short shower instead of baths, repairing leaky faucets, using the dishwasher or washing machine only when fully loaded, or simply turning the faucet off while brushing your teeth.

Third, we need to reduce waste. We need to recycle whenever possible, but should also try to use this waste effectively. For example, grass clippings and food scraps can be made into compost for plants. The average person produces 4.3 pounds of waste every day, but we can reduce that amount by recycling and reusing. 

If we do our part in our own homes, we can help keep the planet from becoming more polluted.

Pollution can be caused from the following sources except_____________.