74. In an area where DDT had been used extensively, the population of birds declined significantly because
(1) Many of the birds eggs laid, did not hatch (2) Birds stopped laying eggs
(3) Earthworms in the area got eradicated (4) Cobras were feeding exclusively on birds
(1) Many of the birds eggs laid, did not hatch (2) Birds stopped laying eggs
(3) Earthworms in the area got eradicated (4) Cobras were feeding exclusively on birds