Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Geological Time ScaleMedium · 45s
The boundary between the Cretaceous and Paleogene is marked by:
TopicGeological Time Scale
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Explanation:The K-Pg boundary (~66 million years ago) is marked by an asteroid impact that caused mass extinction.
Final Answer: Option A — An asteroid impact leading to mass extinction