CFCs contribute to ozone depletion, with significant environmental impacts observed over which region?

CFCs, or chlorofluorocarbons, are a group of man-made chemicals that have historically been used in refrigerants, aerosol propellants, and foaming agents. When these substances are released into the atmosphere, they eventually rise up to the stratosphere, where they are broken down by ultraviolet (UV) radiation, releasing chlorine atoms. These chlorine atoms can then react with ozone (O3) molecules, leading to the depletion of the ozone layer.

Among the regions listed, Antarctica has been particularly affected by ozone depletion due to a combination of factors. The extremely cold temperatures in the Antarctic stratosphere during the winter create polar stratospheric clouds, which provide a surface for chemical reactions that release chlorine from the CFCs. In the spring, when sunlight returns to Antarctica, these reactions accelerate, leading to a significant thinning of the ozone layer, commonly referred to as the "ozone hole."

While ozone depletion is a global issue, the most severe impacts have been observed over Antarctica, making it the correct choice in this context. The unique environmental conditions in this region make it particularly susceptible to the effects of CFCs and other ozone-depleting substances.