Answer:
b) CFCs were released from refrigerants, solvents and aerosols.
Explanation:
CFCs are also known as chlorofluorocarbons- they are made up of chemical elements like fluorine, carbon and chlorine. When released in the atmosphere, they are highly responsible for the depletion of ozone layer. CFCs is used as refrigerants in ACs and refrigerator. During the appliance disposal or any sudden leaks the CFCs are released in the atmosphere,thus damaging the environment. The usage of CFCs as independent solvents and Β in manufacturing of aerosols sprays is also very harmful for the environment.