Question

earth and space science - nuhs
smaller stars will fuse typically up until carbon. at that point the star will eject material as it becomes less and less stable and the gravity can no longer hold on to the mass. eventually all that is left is a white dwarf. no more gasses, just a hot dense center slowly cooling down. this will be our star one day. these are typically much smaller than our sun and are roughly the same size as earth.
the largest stars will continue to fuse elements until it fuses iron. when a stars core is primarily composed of iron, it can no longer produce energy through fusion. the core becomes more dense, as there is no longer an outward force and the star collapses, becoming an increasingly dense center. when that system collapses, all of the material ejects out in a catastrophic event called a supernova, where the star collapses under its own gravity and explodes, releasing a tremendous amount of energy and scattering the newly formed elements into space. the largest of these become black holes, while the smaller become neutron stars.
compare the size of a small main sequence star to its white dwarf final form.
describe a supernova.
which arrow causes the star to collapse on itself?

Explanation:

Smaller stars fuse up to carbon, then eject material and become white dwarfs. Larger stars fuse until iron, then collapse in a supernova. Gravity is the force causing the star to collapse on itself as the outward - pushing fusion force is no longer sufficient when iron is present in the core.

Answer:

The arrow labeled "Gravity" causes the star to collapse on itself.