What type of radiation does the ozone layer mainly protect against?

The ozone layer primarily protects against ultraviolet (UV) radiation from the sun. This layer, located in the stratosphere, contains a high concentration of ozone (O3) molecules, which absorb the majority of the sun's harmful UV radiation. By filtering out these rays, the ozone layer plays a crucial role in safeguarding living organisms on Earth, as excessive exposure to UV radiation can lead to serious health issues, such as skin cancer and cataracts, as well as negative impacts on ecosystems.

The other types of radiation mentioned, such as infrared, X-rays, and gamma rays, are not effectively absorbed by the ozone layer. Infrared radiation, for example, is associated with heat and is not harmful in the same way that UV radiation is. X-rays and gamma rays have much higher energy levels and originate from radioactive materials or cosmic events, which are not significantly limited by the ozone layer's protective capabilities. Therefore, the correct answer highlights the ozone layer's specific protective function against ultraviolet radiation.