Multiple Choice
Why didn't oxygen begin to accumulate in the atmosphere until approximately 1.5 billion years after life appeared on Earth?
A) Early forms of animal life consumed the oxygen.
B) Early forms of plant life consumed oxygen.
C) All the oxygen produced by life went into making the ozone layer.
D) Oxygen produced by life was removed from the atmosphere by oxidation reactions with surface rocks.
E) Oxygen produced by life was removed from the atmosphere by dissolving in the ocean.
Correct Answer:
Verified
Correct Answer:
Verified
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