Answer: A. Plant more trees
Step-by-step explanation: Planting more trees can reduce more pollution that is in the air.
B is wrong because by bottling up more water, it requires more plastic that may be littered on the ground. Raising more livestock is helps the environment through their feces, but it doesn't help global warming trends. Building more schools does not even reduce global warming trends at all. It may do more damage if machines that produces pollution are used during the process of building.
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