The layer of Earth's atmosphere that protects us from the sun's harmful rays is the stratosphere, specifically the ozone layer.

Here's why:

* Ozone layer: This layer within the stratosphere contains a high concentration of ozone gas (O3). Ozone molecules absorb most of the sun's harmful ultraviolet (UV) radiation, particularly the UVB rays that cause sunburn and skin cancer.

While other layers of the atmosphere play roles in protecting us, the ozone layer is the primary shield against these dangerous rays.