Answer:
Iron
Explanation:
Once a star starts fusing iron in its core it gives off very large amounts of energy. Also helium, hydrogen, carbon, oxygen, and silicon still exist in the star in different shells while fusin is taking place at different parts of the star. Right at the surface, hydrogen continues to fuse to helium, as e go further down helium is fusing to carbon and oxygen; right inside the core we have silicon that is fusing with iron. At this point, Iron being of stable atomic structure and quite heavier will no longer be fused into anything because of the quite large amounts of energy and force required to fuse iron atoms. The process comes to a standstill at this point.