Answer:
Supernova
Explanation:
Stars have fixed lifespan. They are born and eventually die when they run out of fuel. An average mass star like sun ends of as white dwarf whereas a high mass star ends up as either neutron star or a blackhole. A high mass star when runs out of fuel first expands to become a supergiant red star and then blows of most of its mass on going supernova. The remnant core is either a neutron star or a blackhole.During supernova, all the heavy elements formed in fusion process is released.