With reference to the planet Earth, consider the following statements:
I. Rainforests produce more oxygen than that produced by oceans.
II. Marine phytoplankton and photosynthetic bacteria produce about 50% of the world's oxygen.
III. Well-oxygenated surface waters contain several times more oxygen as compared to the oxygen present in atmospheric air.
Which of the statements given above is/are correct?
A.I and II
B.II only✓ Correct
C.I and III
D.None of the statements given above is correct
Explanation
Oceans, primarily through marine phytoplankton and photosynthetic bacteria like Prochlorococcus, produce approximately 50-80% of the world's oxygen — far more than rainforests. So Statement I is incorrect (rainforests do NOT produce more than oceans) while Statement II is correct. Statement III is incorrect — oxygen dissolved in surface waters is actually much LESS in concentration than oxygen in atmospheric air (about 21% in air vs. only a few ppm in water). Hence only Statement II is correct.
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