UPSC 2018: Consider the following statements: 1. The Earth's magnetic field has reversed every few hundred thousand years. 2. When the Earth was created more than 4000 million years ago, there was 54% oxygen and no carbon dioxide. 3. When living organisms originated, they modified the early atmosphere of the Earth. Which of the statements given above is/are correct?

The correct answer is option (c): 1 and 3 only. Watch the detailed video explanation in our Sherlocking Prelims course on UnlockIAS.

This question was asked in UPSC CSE Prelims 2018, GS Paper 1, as Question 57. It falls under Geography > Astronomy & Earth–Sun System.

This question is rated "moderate". It requires sound conceptual understanding of the topic.

UPSC has asked 24 questions from Astronomy & Earth–Sun System (under Geography) across multiple years. Visit the topic page to see the full list and year-wise trends.