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In the last decade, the country of Alumba has undergone a ma

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by BTGmoderatorAT » Mon Jan 15, 2018 7:30 am
In the last decade, the country of Alumba has undergone a massive construction boom. In one city, Semanta, hundreds of new buildings have been erected and, as a result, the ambient light at night has increased from 0.10 lux to 10 lux, causing migratory birds flying to alter their traditional path and fly into Semanta, where they often crash into buildings. The mayor believes that to ensure the birds keep to their traditional flight path while flying through Alumba, the city should turn off lights throughout the city at night during the bird’s migratory season, so that ambient light is around 0.10 lux.

Which of the following, is necessary, to evaluate the mayor’s proposal for limiting the amount of night light that Semanta emits?

A The amount of lux necessary to interfere with a bird’s navigational abilities.
B The percent of birds flying through Alumba that are drawn to Semanta’s night light.
C Whether the period in which birds migrate is consistent each year.
D Whether there are any other migratory birds flying through Alumba.
E Whether there are any other cities in Alumba that might also emit enough ambient light to confuse migrating birds.

Is there a strategic approach to this question? Can any experts help?
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Source: — Critical Reasoning |

by DavidG@VeritasPrep » Mon Jan 15, 2018 8:18 am
ardz24 wrote:In the last decade, the country of Alumba has undergone a massive construction boom. In one city, Semanta, hundreds of new buildings have been erected and, as a result, the ambient light at night has increased from 0.10 lux to 10 lux, causing migratory birds flying to alter their traditional path and fly into Semanta, where they often crash into buildings. The mayor believes that to ensure the birds keep to their traditional flight path while flying through Alumba, the city should turn off lights throughout the city at night during the bird’s migratory season, so that ambient light is around 0.10 lux.

Which of the following, is necessary, to evaluate the mayor’s proposal for limiting the amount of night light that Semanta emits?

A The amount of lux necessary to interfere with a bird’s navigational abilities.
B The percent of birds flying through Alumba that are drawn to Semanta’s night light.
C Whether the period in which birds migrate is consistent each year.
D Whether there are any other migratory birds flying through Alumba.
E Whether there are any other cities in Alumba that might also emit enough ambient light to confuse migrating birds.

Is there a strategic approach to this question? Can any experts help?
Notice the scope shift from the first sentence to the second. We learn that the country of Alumba has experienced a massive construction boom. Then we learn about the consequences of new buildings in one city. Well, if there's a similar level of construction/increase in ambient light in other cities in Alumba, then turning out the lights in Semnta isn't going to yield the desired results of returning the birds to their traditional flight path. This is what E would give us.
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