D. All of the above are true.
Used by people is the answer. :-)
It would be d because you could get it again but it would be a different kind
Answer:
In thermodynamics, a closed system can be described as a system which can exchange energy from outside but matter cannot be transferred from such a system. This means that the resources present on the Earth cannot be transferred or replaced and the waste can also not be removed. By understanding the concept of the closed system, humans should recognize the fact that many resources such as minerals present on the Earth cannot be replaced and hence, resources should be utilized effectively in a conserved manner. Also, as waste cannot be removed hence humans should stop forming such waste products which cannot be removed or recycled.
The criteria pollutants are carbon monoxide, lead, nitrogen dioxide, ozone, particulate matter, and sulfur dioxide.
