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amm1812
3 years ago
12

Which was the original source of atmospheric oxygen? Question 4 options: autotrophs cooling of Earth’s crust formation of the oc

eans volcanoes
Biology
1 answer:
Nuetrik [128]3 years ago
5 0

Answer:

The answer is autotrophs

Explanation:

During the early days of the Earths life there was no oxygen but there was plenty of CO2 which the autotrophs took and used as food while discarding the excess which was the oxygen.

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