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UPSC 2025 › Environment & Ecology › Biogeochemical Cycles & Earth Systems

1 question · 2025 · answers as per the UPSC key

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UPSC 2025 · Q40 · Environment & Ecology › Biogeochemical Cycles & Earth Systems · Save

With reference to the planet Earth, consider the following statements : I. Rain forests produce more oxygen than that produced by oceans. II. Marine phytoplankton and photosynthetic bacteria produce about 50% of world's oxygen. III. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air.

Which of the statements given above is/are correct?

(a) I and II
(b) II only
(c) I and III
(d) None of the above statements is correct
Show answer
Answer: (b) II only