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A lake near a village suffered heavy mor...

A lake near a village suffered heavy mortality of fishes within a few day. Consider the following reasons for this?

A

Lots of urea and phosphate fertilizer were used in the crops in the vicinity

B

The area was sprayed with DDT by the aircraft

C

The lake water turned green and stinky

D

Phytoplankton populations in the lake declined initially thereby greatly reducing photosynthesis,

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