The correct answer is (c) excessive use of man-made compounds containing both fluorine and chlorine.
Explanation:
Chlorofluorocarbons (CFCs): These are the primary culprits for ozone depletion. CFCs are widely used in refrigerants, air conditioners, and aerosols. When released into the atmosphere, they rise to the stratosphere where they break down, releasing chlorine atoms which can destroy ozone molecules.
Why other options are incorrect:
(a) excessive use of automobiles:
While automobiles contribute to air pollution, they are not the primary cause of ozone depletion.
(b) excessive formation of industrial units:
While industrial activity can release various pollutants, CFCs are specifically linked to ozone depletion.
(d) excessive deforestation:
Deforestation has negative environmental impacts, but it does not directly contribute to ozone depletion.