The correct answer among the choices presented above is the fourth option. Magnetic minerals are a part of molten rock at mid-ocean ridges. Examples are chromite, magnetite, limenite and ferberite. Hope this answers the question.
Hydrogen. That is how it is continuing to heat, the Hydrogen atoms are fusing to form Hydrogen, but at this point the majority is Hydrogen, eventually it will be majorly Helium, then Carbon.
