Which of the following was part of the ozone depletion problem?

Mining waste

Chlorofluorocarbons

DDT

The answer is Chlorofluorocarbons

Chlorofluorocarbon (CFC) is used as the aerosol propellant. An aerosol is a suspension in the gaseous form of solid or liquid particles. When these compounds reach the stratosphere, UV light affects them and they release chlorine atoms. Chlorine atoms are capable of breaking down ozone molecules. With fewer ozone molecules, the ozone layer becomes thinner and harmful UV light passes through it.