The final remnant of the evolution of a red-giant star that has ejected a planetary nebula is a
A) blue supergiant.
B) neutron star.
C) supernova.
D) white-dwarf star.

Question

Quizplus · Accepted Answer

A red-giant star that has ejected a planetary nebula will eventually shed its outer layers, leaving behind a small, hot core composed mostly of carbon and oxygen. This core will continue to slowly cool and dim over billions of years, eventually becoming a white-dwarf star. Blue supergiants, neutron stars, and supernovae are not the final remnants of a red-giant star that has ejected a planetary nebula.

The Final Remnant of the Evolution of a Red-Giant Star