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anksm22
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Two types of earthworm, one black and one red-brown, inhabit the woods near the town of Millerton. Because the red-brown worm's coloring affords it better camouflage from predatory birds, its population in 1980 was approximately five times that of the black worm. In 1990, a factory was built in Millerton and emissions from the factory blackened much of the woods. The population of black earthworms is now almost equal to that of the red-brown earthworm, a result, say local ecologists, solely stemming from the blackening of the woods.
Which of the following, if true, would most strengthen the conclusion of the local ecologists?
A]The number of red-brown earthworms in the Millerton woods has steadily dropped since the factory began operations.
B]The birds that prey on earthworms prefer black worms to red-brown worms.
C]Climate conditions since 1990 have been more favorable to the survival of the red-brown worm than to the black worm.
D] The average life span of the earthworms has remained the same since the factory began operations.
E]Since the factory took steps to reduce emissions six months ago, there has been a slight increase in the earthworm population.
Why is D wrong . It is also eliminating another cause.
Which of the following, if true, would most strengthen the conclusion of the local ecologists?
A]The number of red-brown earthworms in the Millerton woods has steadily dropped since the factory began operations.
B]The birds that prey on earthworms prefer black worms to red-brown worms.
C]Climate conditions since 1990 have been more favorable to the survival of the red-brown worm than to the black worm.
D] The average life span of the earthworms has remained the same since the factory began operations.
E]Since the factory took steps to reduce emissions six months ago, there has been a slight increase in the earthworm population.
Why is D wrong . It is also eliminating another cause.












