Which part of Earth is primarily responsible for generating Earth’s magnetic field?

• A. Earth’s crust, because most magnetic minerals are located near the surface
• B. Earth’s mantle, because moving rock creates strong electric currents
• C. The liquid outer core, where convecting molten iron drives a geodynamo
• D. The solid inner core, because it is a permanent magnet

Answer: (C)

Verified step by step guidance

1. Understand that Earth's magnetic field is generated by the movement of electrically conductive fluids inside the planet, which creates electric currents and thus magnetic fields through a process called the geodynamo.
2. Recall the internal structure of Earth: the crust (solid outer layer), the mantle (solid but slowly flowing layer beneath the crust), the liquid outer core, and the solid inner core.
3. Recognize that the crust contains magnetic minerals, but their contribution to the global magnetic field is minimal and localized.
4. Note that the mantle is mostly solid rock and does not have the fluid motion necessary to generate strong electric currents for a global magnetic field.
5. Identify the liquid outer core, composed mainly of molten iron and nickel, as the region where convection currents occur, driving the geodynamo that produces Earth's magnetic field.