Q.Which of the following prevents ultraviolet radiations from coming to earth's surface ?

Ozone (the ozone layer) blocks harmful UV radiation.

The ozone (O3) layer in the stratosphere absorbs the Sun's harmful ultraviolet radiation, protecting living organisms on Earth. Depletion of this layer (e.g. by CFCs) lets more UV …

Ozone depletion increases UV exposure, causing skin cancer in humans.

The stratospheric ozone layer absorbs most of the sun's harmful ultraviolet (UV-B) radiation, protecting living organisms. When the ozone layer is depleted (e.g. by CFCs), more UV-B radiation reaches the Earth's surface. Increased UV-B exposure damages skin cel …

Among the choices given, ozone layer depletion is most directly linked to global warming, since a thinner ozone layer allows more radiation to reach and warm the lower atmosphere/surface.

Examine each option:

• Bio-magnification: the increasing concentration of a persistent pollutant (like DDT or heavy metals) up a food chain — this is caused by pesticide/toxin accumulation, not by ozone depletion.
• Forest fires: caused by factors like heat, drought, and human activity, not a direct consequence of ozone depletion. …

The statement is Right: CFCs are used inside electric appliances, chiefly as the refrigerant gas in refrigerators and air conditioners.

Chlorofluorocarbons (CFCs, commonly sold as Freons, e.g. CFCl3, CF2Cl2) are stable, non-toxic, non-flammable, easily liquefiable gases. These properties made them the standard refrigerant used inside the cooling systems of refrigerators and air-conditioners - both electric appliances - for decades, and they were also used as aerosol-spray propellants and in making plastic foams. Their major environmental problem is unrelated to this specific use: once released, CFCs drift into the stratosphere and catalytically destroy ozone (O3) molecules, causing d …

Ozone depletion is linked with global warming, since the same chlorofluorocarbon (CFC) and related halogenated gases that destroy stratospheric ozone are also strong greenhouse gases, and changes to the ozone layer alter how the atmosphere retains heat.

The stratospheric ozone layer absorbs most of the sun's harmful ultraviolet (UV) radiation. Its depletion, mainly by chlorofluorocarbons (CFCs), halons and related compounds, allows more UV radiation to reach the earth's surface. These same ozone-depleting substances are also powerful greenhouse gases in their own right, so their build-up in the atmosphere contributes directly to trapping infrared radiation and warming the planet, i.e., to global warming. The other listed effects — forest fire, eutrophica …