Essayist: When the first prehistoric migrations of humans

Question

Essayist: When the first prehistoric migrations of humans from Asia to North America took place, the small bands of new arrivals encountered many species of animals that would be extinct only 2,000 years later. Since it is implausible that hunting by these small bands of humans could have had such an effect, and since disease-causing microorganisms not native to North America were undoubtedly borne by the new arrivals as well as by the animals that followed them, these microorganisms were probably the crucial factor that accounts for the extinctions.

Which one of the following, if true, most weakens the essayist’s argument?

Which one of the following, if true, most weakens the essayist’s argument?

(A) Animals weakened by disease are not only less able to avoid hunters but are also less able to avoid their other predators.

(B) Human beings generally have a substantial degree of biological immunity to the diseases carried by other species.

(C) Very few species of North American animals not hunted by the new arrivals from Asia were extinct 2,000 years after the first migrations.

(D) Individual humans and animals can carry a disease-causing microorganism without themselves suffering from the disease.

(E) Some species of North American animals became extinct more than 2,000 years after the arrival in North America of the first prehistoric human migrants from Asia.

Source: LSAT

rahimk7 · Answer

ANSWER -C)

This option directly relates human hunting to extinction , Ruling out micro organisms as prime factor behind these extinction

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arvind910619 · Answer

IMO C 
Option C gives accurate reason for extinction of animals .
It also establishes that only very few species who were not hunted by new arrivals of humans became extinct.
Clearly it shows that most of the animal species were hunted by humans and this hunting led to extinction.

YanisBoubenider · Answer

Option C is the strongest "weakener" here:

If very few species not hunted by humans survived, therefore many species lived together with humans newly arrived and were not affected by the microorganism brought by these humans. The argument therefore falls apart and the extinction must have had another crucial factor.

Arro44 · Answer

C is a clear weakener.

"Humans did not hunt species -> species did not go extinct"

Therefore, this gives us reason to believe that human hunting did play a role in the extinction of many species and thereby weakens the original statement.

azamatboden · Answer

I agree with (C) as well, but I chose (E), and that's definitely not a correct choice. It literally just repeats the paragrapoh

VerbalBot · Answer

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Essayist: When the first prehistoric migrations of humans

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Essayist: When the first prehistoric migrations of humans

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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My Rewards