Question

Which of the following statements about air pollution is not true?
a.
Air pollution is caused by natural and human processes.
b.
Carbon monoxide and sulfur oxides are common air pollutants.
c.
Natural components of air, like carbon dioxide, cannot be considered air pollutants.
d.
Primary and secondary pollutants are harmful to human health and the environment.

Answer 1

Answer: c.

Explanation: Natural components like CO2 can be considered air pollutants when their concentrations cause harm (e.g., CO2 as a greenhouse gas, radon as a natural carcinogen). Natural and human-origin substances alike can be pollutants if they damage health or the environment.