Solved UPSC CDS/OTA Question
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Q · Geological Time ScaleMedium · 45s
Arrange the following periods in correct order (earliest to latest): Ordovician Devonian Silurian Carboniferous
TopicGeological Time Scale
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Explanation:Paleozoic Periods order: Cambrian → Ordovician → Silurian → Devonian → Carboniferous → Permian.
Final Answer: Option A — 1, 3, 2, 4