A critical need of society is one that is: unimportant, urgent, exaggerated, optional

Urgent.

Hope it helps yah (◕ᴗ◕✿)

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.