Question

star a is a massive star. what is the most likely end stage of star a? white dwarf neutron star red giant planetary nebula

Explanation:

• White dwarf: White dwarfs are the end - stage of low - mass stars (like the Sun). Massive stars do not end as white dwarfs.
• Neutron star: Massive stars (with a mass between about 8 - 25 times the mass of the Sun) end their lives in a supernova explosion. If the core mass of the star after the supernova is between about 1.4 - 3 times the mass of the Sun, it collapses to form a neutron star.
• Red giant: A red giant is a stage in the evolution of a star (including some massive stars during their intermediate evolution), but it is not the end - stage of a massive star.
• Planetary nebula: A planetary nebula is formed when a low - mass star (like the Sun) ejects its outer layers. Massive stars do not form planetary nebulae.

Answer:

Neutron star