The correct answer is Chlorofluorocarbon. In the 1980s, scientists around the world realized that chlorofluorocarbons (CFCs)—the chemicals used as refrigerants for air conditioners, aerosol sprays, refrigerators, freezers—were depleting the Earth's ozone layer, which blocks the sun's damaging ultraviolet rays. Explanation & Key Takeaways: • Chlorofluorocarbons are various compounds consisting of carbon, hydrogen, chlorine, and fluorine, once used widely as aerosol propellants. • Chlorofluorocarbon is an organic compound that does not occur naturally. • They are man-made gas. It contains carbon, chlorine, and fluorine, produced as a volatile derivative of methane, ethane, and propane. • Commonly known by the name freon, the manufacture of CFCs. In the past 50 years, cfc emission has increased considerably. • It is a colorless, odorless, and chemically non-reactive gas. Moreover, we can find it in the atmosphere as it remains there for a long time. • CFC is also one of those gases involved in the greenhouse effect. • It is particularly harmful because of its destructive reactions with ozone particles, which protects the earth from UV radiations. • Few specialized products are the main source of CFCs.