Hi AnuragRatna,

Let me help you with the first question, about Egyptian bread. The passage presents a relationship between two things: the Egyptians' discovery of leavened bread, and the introduction of a new kind of wheat.

The first half of the passage suggests that the yeasts required to make leavened bread were present before the Egyptians discovered them. Therefore something prevented the Egyptians from noticing the yeasts, and thus being able to make leavened bread. The second half of the passage suggests that the Egyptians' discovery of the yeast roughly coincided with the introduction of a new and preferable kind of wheat (preferable because it was easier to use - it did not require being fired before baking).

The question asks us to find the answer that best establishes a causal relationship between the two things, i.e. which answer clearly reinforces the relationship that one of the things caused the other. Let's review the possible answers:

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.

Answer A is not relevant. We are not interested in what happened with bread consumption after the discovery. Eliminate A.

B. Only when the Egyptians stopped the practice of toasting grain were their stone-lined grain-toasting pits available for baking bread.

Having the pits available for baking bread does not suggest a causal relationship. The pits were likely to have been used for baking all kinds of bread, both leavened and unleavened. Eliminate B.

C. Heating a wheat kernel destroys its gluten, a protein that must be present in order for yeast to leaven bread dough.

Ah, here is something interesting! We are looking for something that was preventing the Egyptians from noticing the yeasts and their action on bread (i.e. as a leavening agent). When the Egyptians switched to a new kind of wheat that did not need to be heated - a process that kept the present yeast from leavening the bread - the yeast was allowed to act as a leavening agent in the bread. Answer C is correct!

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.

This is not relevant. It's nice that the bread had a delicate flavor, but that does not suggest a causal relationship between yeast and bread. Eliminate D.

E. Because the husk of the new variety of wheat was more easily removed, flour made from it required less effort to produce.

This may explain why the Egyptians changed varieties of wheat, but it does not suggest a causal relationship between yeast and bread. Eliminate E.

It is illegal to advertise prescription medications in Hedland except directly to physicians, either by mail or in medical journals. A proposed law would allow general advertising of prescription medications. Opponents object that the general population lacks the specialized knowledge to evaluate such advertisements and might ask their physicians for inappropriate medications. But since physicians have the final say as to whether to prescribe a medication for a patient, inappropriate prescriptions would not become more common.

Which of the following would it be most useful to establish in order to evaluate the argument?

Conclusion: Because PHYSICIANS DECIDE whether to prescribe medications, ADVERTISING TO PATIENTS cannot cause inappropriate prescriptions to become more common.
Assumption: That PATIENTS do not affect what PHYSICIANS DECIDE.

Rephrase the answer choices as STATEMENTS.
Rephrased as a statement, the correct answer choice will either STRENGTHEN or WEAKEN the assumption.

E, rephrased as a statement:
PHYSICIANS WILL GIVE IN TO A PATIENT'S DEMAND for a prescription medication chosen by the patient when the one originally prescribed by the physician fails to perform as desired.
Implication:
PATIENTS DO AFFECT what PHYSICIANS DECIDE, weakening the conclusion that advertising to patients cannot cause inappropriate prescriptions to become more common.

The correct answer is E.