Which statement describes the core's composition?

Which statement describes the core's composition?

• A. The core is primarily silicon and oxygen.
• B. The core is primarily iron and nickel.
• C. The core is primarily carbon and sulfur.
• D. The core is primarily aluminum and magnesium.

Answer: (B)

The core is made mostly of iron and nickel. This is supported by seismic data showing a very dense interior, with the outer part behaving as a liquid and the inner part staying solid under extreme pressures. The iron–nickel composition also explains the Earth’s magnetic field, which arises from convection in the liquid iron of the outer core. Other elements like silicon and oxygen dominate the crust and mantle, while carbon, sulfur, aluminum, and magnesium are present in minerals but do not control the core’s makeup.

The core is made mostly of iron and nickel. This is supported by seismic data showing a very dense interior, with the outer part behaving as a liquid and the inner part staying solid under extreme pressures. The iron–nickel composition also explains the Earth’s magnetic field, which arises from convection in the liquid iron of the outer core. Other elements like silicon and oxygen dominate the crust and mantle, while carbon, sulfur, aluminum, and magnesium are present in minerals but do not control the core’s makeup.