Answer :
The phrase that best describes a point source of air pollution is smokestack releasing dioxins from a plastics factory.
What is point source of pollution?
Point source refers to source of pollution, radiation, waves, fluid or other substance that has one specific location.
Air pollution involves the release of pollutants into the atmosphere.
Therefore, the phrase that best describes a point source of air pollution is smokestack releasing dioxins from a plastics factory because it is from one specific location.
Learn more about point source pollution at: https://brainly.com/question/14819198
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