Answer: two different answers, both correct.
1. When a large star reaches the end of its life, it explodes as a supernova, which can result in the formation of a black hole or a neutron star. Small stars turn into white dwarfs.
2. SAMPLE FROM EDGE:
Late in their lives, smaller stars become red giants that fuse helium into carbon and oxygen. Then they die out as white dwarfs. Instead of red giants, large stars form supergiants that can produce iron through fusion. When the core of a supergiant is entirely iron, fusion stops, which causes the core to collapse. This collapse results in a violent rebound explosion called a supernova.
Step-by-step explanation:
Trust me bro.