Which layer of Earth’s atmosphere is responsible for protecting life by blocking harmful terrestrial solar radiation?

The atmosphere is divided into layers: troposphere, stratosphere, mesosphere, thermosphere, and exosphere.
The stratosphere lies just above the troposphere (from about 10 km to 50 km above Earth’s surface).
Within the stratosphere is the ozone layer, which plays a crucial role in absorbing and filtering out the majority of the Sun’s harmful ultraviolet (UV) radiation.
Without this protective shield, UV rays would cause severe damage to living organisms, including:
Skin cancer and eye damage in humans
Genetic mutations in plants and animals
Disruption of ecosystems
How it works
Ozone (O₃) molecules absorb high-energy UV-B and UV-C radiation.
This absorption prevents most of the harmful radiation from reaching Earth’s surface.
The process also warms the stratosphere, which is why temperature increases with altitude in this layer.
In short, the stratosphere (ozone layer) acts as Earth’s natural sunscreen, making life possible on the planet.