The layer thought to be a liquid metallic region in the interior of the Earth is the outer core.

Here's why:

* Composition: The outer core is primarily composed of iron (Fe) and nickel (Ni), with smaller amounts of other elements like sulfur (S), silicon (Si), and oxygen (O).

* Pressure and Temperature: The immense pressure and incredibly high temperatures (around 4,500°C) in the outer core cause the iron and nickel to behave like a liquid.

* Convection Currents: The liquid metal in the outer core is constantly moving due to convection currents driven by heat from the inner core. This movement generates Earth's magnetic field.

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