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Control over the rabbit population

Expert replies
by kvitkod » Sat Aug 27, 2011 9:26 am
In their attempts to bring the invasive rabbit population under control, Australian authorities have utilized biological rabbit-killing viruses. However, this solution presents a number of problems. One is that the sudden, widespread deaths can put predator populations in danger. Another is that a growing proportion of the rabbit population becomes virus-resistant as the rabbits naturally resistant to a particular virus survive to breed.

Assuming that they are realistic possibilities, which of the following would be a way to extend the effectiveness of using biological rabbit-killing viruses?


(A) Using only biologically stable viruses
(B) Periodically switching to different rabbit-killing viruses
(C) Gradually increasing the virulence of the viruses used
(D) Leaving certain rabbit populations alone for a few years
(E) Breeding rabbits with lower fecundity

[spoiler]OA is B. For me this choice address the second problem only (resistance to the virus). That why I took D that address the first problem as well (to save predators since at least part of the rabbits will be available for them). Where is my flaw?[/spoiler]
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Source: — Critical Reasoning |

by GmatKiss » Sat Aug 27, 2011 11:19 am
Absolutely IMO: B+C should be correct!
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by adi_800 » Sun Aug 28, 2011 11:52 am
Again no change in reasoning...Change of subject and verb...
Same as OG question !!
If the question is having the same reasoning as a ques in OG...then the whole purpose solving that (DUPLICATE) question is lost...
No offense against the original poster but the I m against this practice of justchanging the S n V and not reasoning !!
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by GmatKiss » Sun Aug 28, 2011 10:40 pm
Hi,

Please help to break this down! How is B chosen?

TIA,
GK
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by navami » Mon Aug 29, 2011 6:21 am
B provides a logical reasoning on how the different viruses could be used one after another. If teh viruses are used in alternate manner the resistance would not form easily.

C - is wrong as if this technique is followed the resistance against virus would grow.
E- Out of scope here.
D- not feasible / out of scope
A- Out of scope/ there is no mention of stable/unstable virus
This time no looking back!!!
Navami
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