The correct answer is C. CFCs.
CFCs (chlorofluorocarbons) are a group of man-made chemicals that were once widely used in refrigerators, air conditioners, and aerosol cans. They are also used in some industrial processes. CFCs are very stable and do not break down easily in the atmosphere. When they reach the stratosphere, they are broken down by ultraviolet radiation and release chlorine atoms. These chlorine atoms react with ozone molecules, destroying them.
Nitrous oxide (N2O) is a greenhouse gas that is also a contributor to ozone depletion. It is produced by natural processes, such as the decomposition of organic matter, and by human activities, such as the burning of fossil fuels. Nitrous oxide breaks down in the stratosphere and releases nitrogen oxides, which react with ozone molecules.
SF6 (sulfur hexafluoride) is a greenhouse gas that is also a contributor to ozone depletion. It is used in electrical equipment and as a fire suppressant. SF6 breaks down in the stratosphere and releases sulfur atoms, which react with ozone molecules.
PFCs (perfluorocarbons) are a group of man-made chemicals that are very stable and do not break down easily in the atmosphere. They are used in some industrial processes and as a substitute for CFCs in some applications. PFCs are also a contributor to ozone depletion.
Ozone is a gas that is found in the stratosphere, the layer of the atmosphere that is about 10 to 50 kilometers above the Earth’s surface. Ozone protects life on Earth by absorbing ultraviolet radiation from the sun. Ultraviolet radiation can cause skin cancer and other health problems.
The ozone layer is thinning because of human activities, such as the release of CFCs, nitrous oxide, SF6, and PFCs into the atmosphere. These chemicals break down ozone molecules, destroying them.
The thinning of the ozone layer is a serious problem that affects everyone on Earth. It is important to reduce our emissions of ozone-depleting substances and to protect the ozone layer.