The brightest 100 stars viewed from Earth are mostly not on the main sequence (even though most stars are) because:

A. only high mass stars formed near us in the Galaxy.
B. our region of the Galaxy is very young.
C. the most luminous stars are giants and supergiants that have already finished their main sequence lifetimes.
D. the main sequence is the shortest part of a star's life, so stars don't spend much time there.
E. our region of the Galaxy is very old.


Answer: C. the most luminous stars are giants and supergiants that have already finished their main sequence lifetimes.

Physics & Space Science

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