I chose D. However, I didnt find any strong ground to reject C . Is C wrong because of such an extreme language? Someone please clarify .

I don't think C is in contest at all. It actually strengthens the position that it is unlikely that wheat is domesticated by the tribe.

A - climate, soil supports, but they may have not known wheat
B - previous tribe abilities may not be inherited by present
C - strengthens that the tribe did not successfully domesticate wheat
E - its about the requirements, does not imply success in domestication
D - Right answer

Need to read the last line of the question:

[i]The Kazazi did not have unique names for varieties of wheat, however, so it is unlikely that the Kazazi were able to domesticate wheat.[b]
[/b][/i]

Here the statement in the conclusion says >> since wheat was not given unique names, therefore, no unique names for wheat.

question requires us to find statement most undermines the conclusion : which means wheat was domesticated but no unique name given to wheat



C) Tribes only give unique names to​ crops that they have successfully domesticated.
if tribe did not give name to wheat that means wheat was not successfully domesticated

D) The Kazazi did not have unique names for different varieties of potatoes or lettuce, crops the tribe is known to have domesticated.
here, it says with examples of potato & lettuce being domesticated they were not given unique names, in the same fashion even wheat would have not got a unique name even though it was domesticated.


i hope it helps.

VERITAS PREP OFFICIAL SOLUTION:

If you break down the logical flaw in the argument, it is one of generalization - the argument essentially says that "the tribe gave specific names to one type of crop it domesticated, so if it didn't have a special name for a type of crop it didn't domesticate it."

In order to weaken an argument with a generalization flaw, you want to show that that one data point isn't indicative of the whole. And choice D does just that: it shows two other types of crops that didn't have special names but were domesticated, showing that the "domesticated and had names" link is an outlier, not the rule. Choice D is therefore correct.

Among the incorrect answer choices: choice A is a long way away from "domesticating" wheat - since the argument states that the Kazazi was the first tribe to domesticate corn, it shows that just having good conditions doesn't mean that those conditions are anywhere near sufficient to domesticate a crop. So A doesn't have an impact on the conclusion. Choice B is similar: just because wheat had already been domesticated for the first time somewhere else on the planet doesn't mean that the Kazazi would have been able to do it on their own. Choice C is out of scope: the Kazazi did not have special names for wheat, so knowing the circumstances under which tribes DID have special names for crops is irrelevant. And choice E, if anything, strengthens the argument by suggesting essentially that if you just figured out how to domesticate corn, you still have a long way to go to domesticate wheat.
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