Solved UPSC CDS/OTA Question
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Q · Geological Time ScaleMedium · 45s
Statement: Stromatolites are biogenic sedimentary structures.
TopicGeological Time Scale
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Explanation:Stromatolites are layered bio-chemical accretions by cyanobacteria.
Final Answer: Option A - Correct