The correct option is Ozone.
Explanation
The Earth's atmosphere consists of a mixture of gases, each serving specific functions essential for the sustenance of life and the regulation of the planet's temperature. While nitrogen and oxygen constitute the majority of the atmosphere by volume, trace gases play critical roles in radiation balance and protection.
Option Analysis
- Carbon Dioxide: This gas is meteorologically significant because it is transparent to incoming solar radiation but opaque to outgoing terrestrial radiation. It absorbs heat but does not filter ultraviolet rays.
- Oxygen: While essential for respiration and combustion, molecular oxygen ($O_2$) is not the primary filter for ultraviolet radiation, although it is involved in the chemical process of ozone formation.
- Ozone: Ozone ($O_3$) is found in very small quantities in the atmosphere, with the highest concentration occurring in the stratosphere (between 10 and 50 km altitude). It acts as a crucial shield by absorbing the sun's harmful ultraviolet (UV) radiation, preventing it from reaching the Earth's surface.
- Nitrogen: As the most abundant gas, nitrogen acts as a diluent and regulates combustion, but it does not possess properties to filter ultraviolet rays.
Key Takeaway
Ozone is the specific atmospheric component located in the stratosphere that absorbs ultraviolet radiation, protecting the biosphere from its damaging effects.