Correct Answer: CFCs (chlorofluorocarbons)

Solution : The correct answer is (C) CFCs (chlorofluorocarbons).

The main cause of the hole in the ozone layer is the release of certain chemicals known as chlorofluorocarbons (CFCs). CFCs were commonly used in various industries, such as aerosol propellants, refrigeration, and air conditioning. When released into the atmosphere, CFCs can reach the stratosphere, where they undergo chemical reactions triggered by ultraviolet (UV) radiation from the Sun.

These reactions break down the CFC molecules and release chlorine atoms. The chlorine atoms then catalytically destroy ozone molecules, leading to the thinning of the ozone layer. This thinning is particularly prominent in certain regions, such as over Antarctica, where a "hole" in the ozone layer has been observed.