You are very right to have a problem. It is a hard question
IMO C
Sorry but I am not sure with my answer! Ans seek for the OA and explanations...

IMO C
Toasting the wheat destroyed the protein which hampered the yeast to do its thing even though it was added accidentally prior to 3k BC. With the new variety being introduced arnd 3K, toasting was nt required and therefore leavened bread could be used.

IMO C.

Basically, the passage speaks about the coincidence of egyptians finding a new variety of wheat with leavening bread. The first half of the passage suggests that the required yeasts where present centuries before egyptians finally discovered it. That implies that somehting was preventing Egyptians to notice the leavening of the bread and finding the yeast.
The second paragraph suggests that when egyptians finally found yeast, it was around the same time when they switched from using a type of grain to a preferable type of grain which did not require toasting of the grain.
With this in mind, lets look at the options..


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. --> irrelevant. we are not interested in the usage of the bread after it's discovery.

B. Only when the Egyptians stopped the practice of toasting grain were their stonelined grain-toasting pits available for baking bread. --> seems tricky, but lack of time of baking breads is not where mentioned in the paragrapgh. hence, incorrect.

C. Heating a wheat kernel destroys its gluten, a protein that must be present in order for yeast to leaven bread dough. --> correct. as mentioned in the first paragraph, we need to find 'something' that was preventing egyptians to notice. now the reason why these guys switched to a new variety of wheat was because they were heating the old variety of wheat. this particualr argument says that if we heat the wheat, the yeast gets destroyed. and thats the specific reason why egyptians didnt notice the leavening coz the thing that they had to notice was never there in the first place becuase it got destroyed in the heat.

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. -->huh?? are we tasting the wheat?? irrelevant

E. Because the husk of the new variety of wheat was more easily removed, flour made from it required less effort to produce. --> it just suggest why egyptians moved from the old variety of wheat to the new ones..

Dean Jones wrote:Hi Friends,

I am having problems in solving the following CR question. Please help.

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.

OA after some discussions.

Regards
Deano.

IMO C. other choices doesn't relate to the coincidence Yeasts capable of leavening bread and whaet variety ..without toasting a grain.

OA is C

(Just for fun)

I think it's just because only C has the key word "yeasts"