The Earth's core, specifically the outer core, is responsible for the planet's magnetic field.

Here's why:

* Outer core: This layer is composed of liquid iron and nickel, constantly moving due to convection currents. This movement creates electric currents, which in turn generate a magnetic field.

* Inner core: While solid, the inner core's intense heat and pressure also contribute to the overall magnetic field.

The Earth's magnetic field acts as a protective shield, deflecting harmful solar radiation and protecting life on the planet.