Multiple Choice
Once oxygen started to be manufactured by cyanobacteria, why did it take so long to build up to significant levels?
A) initially most of the oxygen escaped into space
B) oxidation of surface rock and ocean minerals occurred
C) initially most of the oxygen produced dissolved in the oceans
D) initially most of the oxygen was converted into water by reaction with hydrogen
Correct Answer:

Verified
Correct Answer:
Verified
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