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Assertion (A) : Cyanobacteria are photos...

Assertion (A) : Cyanobacteria are photosynthetic blue green algae which produce oxygen.
Reason (R) : Cyanobacteria played a key role in the changes of atmospheric oxygen levels from So anaerobic to acerobic during the geologic periods.

A

(A) is correct and (R) explains (A)

B

Both (A) and (R) are wrong

C

(A) is correct and (R) does not explains (A)

D

(A) is wrong and (R) is correct

Text Solution

Verified by Experts

The correct Answer is:
A, C, D
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