Multiple Choice
What do we expect for the lifetime of Population III stars?
A) These stars were almost pure hydrogen and helium, and such stars use only the hydrogen fusion reaction. Therefore, we expect their lifetimes were long.
B) These stars were characterized by almost zero metallicity, and such stars require large masses to collapse. With these large masses, we expect that their lifetimes were long.
C) These stars were characterized by almost zero metallicity, and such stars require large masses and consequently high central temperatures to collapse. With high central temperatures, we expect their lifetimes were short.
D) Since they were formed as early as 400 million years after the Big Bang, and we still find large numbers of them currently in existence, we know that their lifetimes are extremely long.
Correct Answer:

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Correct Answer:
Verified
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