Correct Option: C

The ozone layer is a layer in Earth’s atmosphere containing relatively high concentrations of ozone (O3). The ozone layer absorbs 97–99% of the Sun’s mediumfrequency ultraviolet light (from about 200 nm to 315 nm wavelength), which potentially damages exposed life forms on Earth. Although the concentration of the ozone in the ozone layer is very small, it is vitally important to life because it absorbs biologically harmful ultraviolet (UV) radiation coming from the sun. Extremely short or vacuum UV (10-100 nm) is screened out by nitrogen.