Although They Are Not Directly Toxic to Living Organisms,chlorofluorocarbons (CFCs)have

Multiple Choice

Although they are not directly toxic to living organisms,chlorofluorocarbons (CFCs) have had unanticipated effects on Earth's atmosphere.The ecological impacts of CFCs will be

A) relatively benign, because even as secondary pollutants their toxicity remains low.
B) limited to the terrestrial ecosystem only.
C) limited to high-altitude communities where ultraviolet radiation is more intense.
D) uniformly serious, affecting almost all ecosystems and trophic levels.