Solved UPSC CDS/OTA Question
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Q · Geological Time ScaleMedium · 45s
Consider the following statements: The Precambrian Eon accounts for about 88% of Earth’s geological history. The Phanerozoic Eon follows the Precambrian Eon. The Paleozoic Era is part of the Precambrian Eon. Which of the statements given above is/are correct?
TopicGeological Time Scale
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Q 1 / 30Next question →
Step-by-Step Solution
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Explanation:
Statement 1 is correct: The Precambrian is the longest Eon (~88% of Earth’s history).
Statement 2 is correct: The Phanerozoic comes after the Precambrian.
Statement 3 is incorrect: The Paleozoic Era is within the Phanerozoic Eon, not Precambrian.
Final Answer: Option A — 1 and 2 only