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Standard XII
Biology
Question

Assertion :The first living organisms were heterotrophs. Reason: They were surrounded by performed organic molecules which they used as food.
  1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
  2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
  3. Assertion is correct but Reason is incorrect
  4. Both Assertion and Reason are incorrect

A
Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B
Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C
Assertion is correct but Reason is incorrect
D
Both Assertion and Reason are incorrect
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Solution
Verified by Toppr

Bacteria have been the very first organisms to live on Earth. They made their appearance 3 billion years ago in the waters of the first oceans. At first, there were only anaerobic heterotrophic bacteria (the primordial atmosphere was virtually oxygen-free).
So the correct option is ' Both assertion and reason are correct and the reason is the correct explanation for assertion’.

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