Question

The core of the earth is made up of mainly

• A. Gold
• B. Silver
• C. Iron
• D. Mercury

Answer 1

The correct option is C

Iron

Earth's core:

1. Earth's interior is layered like an onion.
2. The solid iron-nickel inner core — today $1200$ kilometers in radius, or about three-quarters the size of the moon — is surrounded by a fluid outer core of molten iron and nickel about $2400$ kilometers thick.
3. Unlike the rich mineral- crust and mantle, the core is made almost entirely of metal—specifically, iron and nickel.
4. The shortcut used for the core's iron-nickel alloys is simply the elements' chemical symbols—NiFe.

Thus, the correct option is option C.