Which section of the atmosphere contains the highest concentration of ozone?

The section of the atmosphere that contains the highest concentration of ozone is the stratosphere. This layer is located above the troposphere and below the mesosphere, and it plays a critical role in absorbing the majority of the sun's harmful ultraviolet (UV) radiation. The presence of ozone in the stratosphere creates the ozone layer, which serves as a protective barrier for life on Earth by filtering out these high-energy UV rays.

Ozone is formed through a photochemical reaction involving oxygen molecules and UV light, leading to a concentration of ozone at higher altitudes in the stratosphere compared to other atmospheric layers. While the troposphere does contain some ozone, its concentration is significantly lower and affected by human activities and pollution. The mesosphere and exosphere contain even less ozone, with the exosphere being the outermost layer of the atmosphere where gases are far more dispersed. Therefore, the stratosphere is uniquely important as it houses the ozone layer, making it the correct answer.