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The graph given below represents the eff...

The graph given below represents the effect of sewage discharge on some important characteristics of river.
Select the correct option with respect to the peaks A and B.

A

Peak A- Sharp increase in BOD, disappearance of clean water organisms
Peak B- Increase in dissolved oxygen, reappearance of clean water organisms

B

Peak A- Increase in dissolved oxygen, reappearance of cleanwater organisms
Peak B- Sharp increase in BOD, appearance of clean water organisms

C

Peak A- Sharp increase in BOD, appearance of clean water organisms
Peak B- Increased number in dissolved oxygen, disappearance of clean water organisms

D

Peak A- Increased number of anaerobic bacteria, disappearance of clean water organisms
Peak B- Sharp decline in dissolved `O_(2)`, reappearance of clean water organisms

Text Solution

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The correct Answer is:
A
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