Correct Option
The Earth's core, located beneath the mantle, is predominantly composed of iron (Fe). Nickel (Ni) is another significant constituent, leading to the core sometimes being referred to as the 'Nife' layer. This innermost layer is further differentiated into an outer liquid core and an inner solid core, both of which are rich in iron.
Incorrect Options
(a) Aluminium: Aluminium is a major element found in the Earth's crust, forming various silicate minerals, but it is not a primary component of the core.
(b) Chromium: Chromium is present in the Earth's composition but is not a major constituent of the core. It is typically found in trace amounts or as part of specific mineral formations in other layers.
(d) Silicon: Silicon is a fundamental element of the Earth's crust and mantle, forming the basis of silicate minerals. However, it is not a dominant element in the core's composition.