Question

the presence of which element would indicate that a star is going through a high - mass star life cycle as opposed to a low - mass star life cycle?
o hydrogen
o carbon
o helium
o iron

Explanation:

Low - mass stars end their lives after producing carbon and oxygen through nuclear fusion. High - mass stars can continue fusion reactions beyond carbon and oxygen production. Iron is the end - product of nuclear fusion in high - mass stars. Once iron is present in the core of a star, it signals that the star is in a late stage of a high - mass star life cycle as fusion of iron does not release energy and leads to the star's collapse. Hydrogen, carbon, and helium are present in both low - mass and high - mass stars at different stages, but iron is characteristic of high - mass star life cycles.

Answer:

D. iron