What is the final stage in the given sun-like star life cycle?

• A. White dwarf
• B. Nebula
• C. Red giant
• D. Supernova

Answer: (D)

The concept here is how stars with Sun-like masses end their lives. After a star like the Sun uses up hydrogen in its core, it swells into a red giant and then sheds its outer layers. The remaining hot core becomes a white dwarf, which then slowly cools over long time scales. A nebula refers to the surrounding gas ejected during this process, not the final stellar remnant. A red giant is an earlier, enlarged stage, and a supernova is the explosive death of much more massive stars. So for a sun-like star, the final stage is a white dwarf.