Solved UPSC CDS/OTA Question
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Q · Geological Time ScaleMedium · 45s
Which event separates the Archean from the Proterozoic?
TopicGeological Time Scale
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Explanation:The Great Oxidation Event (~2.4 Ga) marks the Archean-Proterozoic boundary.
Final Answer: Option A — Great Oxidation Event