Atmospheric Structure and Ozone

Ozone gas is a layer which is present in the stratosphere and absorbs the harmful ultraviolet radiation. The ozone depletion takes due to the excessive emission of (CFCs). CFC find wide use as refrigerants. CFCs discharged in the lower part of atmosphere move upward and reach stratosphere. In stratosphere, UV rays act on them releasing Cl atoms. Cl degrades ozone releasing molecular oxygen, with these atoms acting merely as catalysts; Cl atoms are not consumed in the reaction. Hence, whatever CFCs are added to the stratosphere, they have permanent and continuing affects on ozone levels. This has resulted in formation of a large area of thinned ozone layer, commonly called as the ozone hole.

Chlorofluorocarbons are the compounds which are used as coolants in the air conditioning systems, refrigerators, coolers, etc. The CFCs, when released into the atmosphere, react with UV rays to form chlorine atoms which destroy the ozone layer and results in the thinning out of the ozone layer also known as the ozone hole.

Chlorofluorocarbon compounds are released from automobiles, refrigerators, etc. These compounds cause an increase in atmospheric temperature causing global warming.

The presence of CFCs in the atmosphere results in the depletion of the ozone layer. They are used as coolants in refrigerators, coolers, etc. The CFCs causes the breaking of the ozone molecule which forms the oxygen radical and O$ _2$. The depletion of the ozone layer results in the penetration of the harmful UV radiations from the sun into the Earth's atmosphere. 

Ozone is an inorganic molecule formed by the three molecules of oxygen with the chemical formula O$ _3$. It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope O$ _2$ and more reactive molecule.

When oxygen molecules absorb ultraviolet photons and undergo photolysis, ozone is obtained
$3O _2 \xrightarrow [photolysis]{UV : light} 2O _3$.

Ozone shields the surface of the earth from ultraviolet (UV) radiation from the sun. Ozone layer reduces the chances of skin cancer.

40 to 50% depletion in ozone layer occurs in the South polar region.
Ozone is destroyed by collisions with other atoms and molecules.
The large scale destruction of the stratospheric ozone first came into focus in 1987 through the experiments in antarctica.

Depletion of ozone layer is mainly due to Chloroflorocarbons.
Note:
The following describes the destruction of the ozone by chlorofluorocarbons.
Chlorofluorocarbons contains the chlorine molecule which reacts with ozone (O$ _3$) molecule and splits into O$ _2$ and O molecules.
Chlorofluorocarbons are used in refrigerators, air conditioners and aerosol sprays. They damage the ozone layer of the atmosphere.

The presence of CFCs in the atmosphere results in the depletion of the ozone layer. The chemical formula of this substance is CF$ _2$Cl$ _2$. They are used as coolants in refrigerators, coolers, etc. The CFCs causes the breaking of the ozone molecule which forms the oxygen radical and O$ _2$. The depletion of the ozone layer results in the penetration of the harmful UV radiations from the sun into the Earth's atmosphere. 

The correct answer is Stratosphere. Option C

Chlorofluorocarbons or Chlorofluoromethane are also known as freon or aerosols. They are chemicals used as refrigerants, propellants and solid plastic foams. These chemicals are also released as aerosols by jets flying at high altitudes. Along with nitrogen oxides, chlorofluorocarbons react with ozone of ozonosphere and depletes the same. Chlorofluorocarbons release reactive chloride which directly reacts with ozone molecules setting a chain reaction.

CFCs (Chlorofluorocarbons) are the most well-known pollutants responsible for the catalytic destruction of the ozone layer in the stratosphere.