Chlorofluorocarbons or CFCs, are the chemicals primarily responsible for the depletion of the ozone layer. These synthetic compounds were once widely used in refrigeration, air conditioning and aerosol sprays. When released, they migrate to the stratosphere, where solar radiation breaks them down, releasing chlorine atoms that aggressively destroy ozone molecules in a repetitive and highly damaging chemical chain reaction. ANSWER: (B) Chlorofluorocarbons