The correct option is It contains the Ozone layer..
Explanation
The atmosphere consists of concentric layers of air with varying density and temperature. The stratosphere is the second major layer of the atmosphere, situated immediately above the troposphere and separated from it by the tropopause.
Option Analysis:
- It lies below the Troposphere. is Incorrect: The stratosphere lies above the troposphere. The troposphere is the lowest layer of the atmosphere, extending from the Earth's surface up to the tropopause.
- It extends up to 80 km. is Incorrect: The stratosphere extends up to a height of 50 km. The layer that extends up to 80 km is the mesosphere, which lies directly above the stratosphere.
- It contains the Ozone layer. is Correct: The stratosphere contains the ozone layer. This layer is crucial as it absorbs ultra-violet (UV) radiation from the sun, shielding life on Earth from harmful energy.
- Temperature decreases with altitude in this layer. is Incorrect: Unlike the troposphere, where temperature decreases with altitude, the temperature in the stratosphere increases with altitude. This phenomenon, known as temperature inversion, occurs because the ozone layer absorbs UV radiation, heating the surrounding air.
Key Takeaway:
The stratosphere is characterized by the presence of the ozone layer and a temperature profile where temperature increases with height, extending up to 50 km above the Earth's surface.