CR 300: Yeasts capable of leavening

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CR 300: Yeasts capable of leavening

by binit » Sun Jun 28, 2015 12:30 am
Q. Yeasts capable of leavening bread are widespread, and in the many centuries during which the ancient Egyptians made only unleavened bread, such yeasts must frequently have been mixed into bread doughs accidentally. The Egyptians, however, did not discover leavened bread until about 3000 B.C. That discovery roughly coincided with the introduction of a wheat variety that was preferable to previous varieties because its edible kernel could be removed from the husk without first toasting the grain.

Which of the following, if true, provides the strongest evidence that the two developments were causally related?
A. Even after the ancient Egyptians discovered leavened bread and the techniques for reliably producing it were well known, unleavened bread continued to be widely consumed.
B. Only when the Egyptians stopped the practice of toasting grain were their stonelined grain-toasting pits available for baking bread.
C. Heating a wheat kernel destroys its gluten, a protein that must be present in order for yeast to leaven bread dough.
D. The new variety of wheat, which had a more delicate flavor because it was not toasted, was reserved for the consumption of high officials when it first began to be grown.
E. Because the husk of the new variety of wheat was more easily removed, flour made from it required less effort to produce.

[spoiler]OA: C[/spoiler]

Pls reply with some good reason / point.
Source: — Critical Reasoning |

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by GMATGuruNY » Sun Jun 28, 2015 5:42 am
binit wrote:Q. Yeasts capable of leavening bread are widespread, and in the many centuries during which the ancient Egyptians made only unleavened bread, such yeasts must frequently have been mixed into bread doughs accidentally. The Egyptians, however, did not discover leavened bread until about 3000 B.C. That discovery roughly coincided with the introduction of a wheat variety that was preferable to previous varieties because its edible kernel could be removed from the husk without first toasting the grain.

Which of the following, if true, provides the strongest evidence that the two developments were causally related?
A. Even after the ancient Egyptians discovered leavened bread and the techniques for reliably producing it were well known, unleavened bread continued to be widely consumed.
B. Only when the Egyptians stopped the practice of toasting grain were their stonelined grain-toasting pits available for baking bread.
C. Heating a wheat kernel destroys its gluten, a protein that must be present in order for yeast to leaven bread dough.
D. The new variety of wheat, which had a more delicate flavor because it was not toasted, was reserved for the consumption of high officials when it first began to be grown.
E. Because the husk of the new variety of wheat was more easily removed, flour made from it required less effort to produce.
The correct answer choice must link the introduction of a WHEAT VARIETY WITH AN EDIBLE KERNEL THAT COULD BE REMOVED WITHOUT TOASTING to the DISCOVERY OF LEAVENED BREAD.
Answer choice C:
Heating a wheat kernel destroys its gluten, a protein that must be present in order for yeast to leaven bread dough.
Implication:
Since the edible kernel could be removed WITHOUT TOASTING, it would retain its gluten, enabling yeast to LEAVEN THE BREAD -- a clear link between the introduction of the wheat variety with the edible kernel and the discovery of leavened bread.

The correct answer is C.
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by binit » Sun Jun 28, 2015 7:32 am
Thanks for clear explanation, Mitch.
I got this prob correct but there was a gap in understanding.
Do you find this Question GMAT-like? If yes, which category should it lie? Strengthen?

~Binit.

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by GMATGuruNY » Mon Jun 29, 2015 6:36 am
binit wrote:Thanks for clear explanation, Mitch.
I got this prob correct but there was a gap in understanding.
Do you find this Question GMAT-like?
This is an official CR from GMATPrep.
If yes, which category should it lie? Strengthen?
Correct.
The OA must STRENGTHEN the conclusion by providing the strongest evidence that the two developments were causally related.
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by nikhilgmat31 » Thu Jul 30, 2015 2:48 am
Answer is C.

In simple terms - with old variety of wheat which was toasted. It destroys the gluten & will not allow yeast leaven the bread.


so with new variety of bread they need not to toast bread which prevents gluten & allows yeast to leaven bread.