Why does nuclear fusion stop advancing beyond Iron in the core of a supergiant?

Answer

Fusing iron consumes energy rather than releasing it

Iron nuclei are the most stable in the universe; fusing elements lighter than iron releases energy, but fusing iron consumes energy, thus removing the outward support against gravity.

Why does nuclear fusion stop advancing beyond Iron in the core of a supergiant?
Elementhydrogencompositionstarsupergiant