Answer: b) the number of sources of pollution
Explanation:
Pollution is the introduction of harmful or toxic substances in the environment of a substance.
Point source pollution is the pollution from a single identifiable source. Example of a point source pollution is pollutants from factories and sewage treatment plants.
Non point source pollution is from a number of sources and we may not identify all of the sources.Thus non point pollution is also termed as diffused pollution. Example of a non point source pollution is fertilizers and pesticides from agricultural lands.
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