Inference : Need valid justification for correct answer

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Source : Princeton Practice question book

Greg: the dramatic rise in illegal immigration in the last decade is evidenced by the fact that 7 of every 10 small business owners reports knowingly employing ,or knowing a small business owner who knowingly employs, an illegal immigrant.

Jackson: But the statistics show that 10 years ago, approximately 8% of small businesses employed an illegal immigrant, with 1 in 12 doing so. So if the average small business owner knew 20 other small business owners, it is unlikely that they would not have known ne who employs an illegal immigrant.

Jackson's argument is designed to support which of the following conclusions?

A.If more than 8% of small businesses employ an illegal immigrant, the 7 of 10 figure greg cites must be too high.
B.The current percentage of small businesses employing an illegal immigrant must be greater than it was a decade ago
C.If statistics show that 8% of small businesses employed an illegal immigrant, the actual percentage is likely much higher.
D.That 7 of 10 small business owners know someone who employs an illegal immigrant does not demonstrate that illegal immigration has increased in the last 10 years.
E.It is likely that the owners Greg cities would have openly acknowledged breaking the law

[spoiler]OA: D ;IMO: D[/spoiler]

Even though I nailed down to the correct answer,I am hardly able to explain myself how D is the correct answer.
can you please provide me valid justification for correct answer ?
Source: — Critical Reasoning |

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by GMATGuruNY » Sat Oct 01, 2011 3:06 pm
gauravgundal wrote:Source : Princeton Practice question book

Greg: the dramatic rise in illegal immigration in the last decade is evidenced by the fact that 7 of every 10 small business owners reports knowingly employing ,or knowing a small business owner who knowingly employs, an illegal immigrant.

Jackson: But the statistics show that 10 years ago, approximately 8% of small businesses employed an illegal immigrant, with 1 in 12 doing so. So if the average small business owner knew 20 other small business owners, it is unlikely that they would not have known ne who employs an illegal immigrant.

Jackson's argument is designed to support which of the following conclusions?

A.If more than 8% of small businesses employ an illegal immigrant, the 7 of 10 figure greg cites must be too high.
B.The current percentage of small businesses employing an illegal immigrant must be greater than it was a decade ago
C.If statistics show that 8% of small businesses employed an illegal immigrant, the actual percentage is likely much higher.
D.That 7 of 10 small business owners know someone who employs an illegal immigrant does not demonstrate that illegal immigration has increased in the last 10 years.
E.It is likely that the owners Greg cities would have openly acknowledged breaking the law

[spoiler]OA: D ;IMO: D[/spoiler]

Even though I nailed down to the correct answer,I am hardly able to explain myself how D is the correct answer.
can you please provide me valid justification for correct answer ?
When a CR features two speakers, the two speakers almost invariably will come to OPPOSITE CONCLUSIONS.
Otherwise, the second speaker would serve no purpose.

Greg's conclusion: That ONE statistic -- 7 of every 10 small business owners reports knowingly employing, or knowing a small business owner who knowingly employs, an illegal immigrant -- is evidence of the rise in illegal immigration.

Jackson comes to the OPPOSITE CONCLUSION: That the statistic offered by Greg is NOT evidence of the rise in illegal immigration. (Jackson offers statistics of his own to support his position.)

Answer choice D describes Jackson's conclusion: That 7 of 10 small business owners know someone who employs an illegal immigrant -- the ONE statistic offered by Greg -- does NOT demonstrate that illegal immigration has increased in the last 10 years.

The correct answer is D.
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by 1947 » Sat Oct 01, 2011 10:01 pm
Nice explanation Mitch...Thanks
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by sl750 » Mon Oct 03, 2011 12:34 am
This argument is similar to an OG argument about prisoners. Only, there the answer choice was more trickier to identify