anything humans add to the atmosphere and oceans any substance that is harmful to the environment any substance that is a waste product of industry a substance that does not break down over time
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which of these best defines the term "pollutant"?
Possibilities:
- anything humans add to the atmosphere and oceans
- any substance that is harmful to the environment
- any substance that is a waste product of industry
- a substance that does not break down over time

any substance that is harmful to the environment