Great amounts of energy are released in the core of a star as lighter elements combine and form heavier elements during the process of nuclear fusion.
<u>Explanation:</u>
Nuclear fusion is the defined as the fusion or combination of many lighter elements to form heavier element.
Example: Two hydrogen nuclei combine or fuse to form a helium. The greatest amount of energy in star is its hydrogen which gets exhausted consequently resulting in burning of helium and forming heavier elements.
