Question

After its main sequence existence, a medium-sized star, like our Sun, will become a _____.

protostar
red dwarf
white dwarf
red giant
red supergiant

Answer 1

Red Giant is the answer

Answer 2

After the Sun finishes its main sequence, its fuel will run out. That will cause the Sun to expand until becoming a red giant. It would probably engulf the Earth, but that's millions of years away, so we won't be alive.

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