Which category includes brown dwarfs, white dwarfs, neutron stars, novae, and black holes as possible end states?

• A. Stars
• B. Planets
• C. Galaxies
• D. Comets

Answer: (A)

The idea being tested is how stars end their lives and the various remnants or phenomena that can result from stellar evolution. Brown dwarfs are objects formed like stars but never ignite sustained hydrogen fusion, placing them in the family of stellar objects rather than planets. White dwarfs, neutron stars, and black holes are classic end states: white dwarfs are the cooled remnants of low- to intermediate-mass stars, neutron stars and black holes come from the collapse of more massive stars after supernovae, and novae are dramatic eruptions that can occur on the surface of a white dwarf in a binary system. Together, these are all tied to stellar processes, so the category that fits them is Stars. Planets, galaxies, and comets are not end states of stars.