Q.Name the most harmful radiation entering the Earth's atmosphere from the outer space.

[!TLDR] Ultraviolet rays are the most harmful radiation reaching the Earth's atmosphere from outer space that this …

Section 13.3.5 identifies the Sun as the most important natural source of ultraviolet rays reaching Earth's atmosphere, most of which are fortunately absorbed by the ozone layer before reaching the surface -- implying that without this absorption, UV exposure at ground level would be significantly more intense and harmful. UV rays are also grouped, along with X-rays and gamma rays, as ionizing radiation (section 13.3.7's 'Ionizing radiations' box), capable of damaging living cells; but of these three, it is specifically ultraviolet radiation from the Sun -- a genuinely continuous, everyday flux entering t …

Recall that section 13.3.5 specifically calls out solar ultraviolet radiation as needing the ozone layer's protective absorption, marking it as the harmfu …

Answering 'gamma rays' or 'X-rays' by over-generalising the shared 'ionizing radiation' category, without noting that the text specifically discusses UV (not gamma/X-ray) as the ongo …