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This question belongs to Biology GK Chapter Wise Gentics And Evoloution

Gentics and Evoloution

?

How is free oxygen present into the earth's atmosphere, whereas there was no free oxygen at the time of origin of life?

A) By catalytic activity of animals B) By photosynthetic activity C) By heating of earth D) None of the above

Answer & Solution

Correct Answer: Option B

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Question posted by Examveda

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