Choose the best answer to complete each sentence.

They are working to preserve the delicately balanced                of these wetlands. 

Mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions.

Burning garbage ________dangerous gases to the environment, and this may lead to global warming.

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The campaign ________things like water bottles and aluminum cans into new, useful objects like park benches, bikes, etc.

Choose the best answer to complete each sentence.

Recycling provides a method of reducing the amount of waste materials that gets to the landfills – thus ______ it less probable for environmental pollution to take place.

Choose the best answer to complete each sentence.

Forest biodiversity is threatened by illegal                  carried out globally. 

Mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions.

Trees not only bring nature to urban areas, but they also help clean the air by absorbing pollutants, ______oxygen, ______water, and growing food.

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We get the energy we require for our everyday needs from many sources, but not all of them are ___________.

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Sometimes it’s better not to buy something new, and buy ________one instead.