Carcass your help is needed.

Why not E?

First of all read, I strongly suggest to you to do ASAP, my post about RC here (it will be the definitive guide soon with several chapters - - already three are done) https://gre.myprepclub.com/forum/gre-readi ... 20658.html

see my thinking spectrum about main idea.

Now,


It might seem illogical that the development of modern currency rests on a scientific discovery, but the invention of the "touchstone" allowed ancient societies to create a standard by which valuable metals could be judged. In its most basic form, a touchstone is any dark, finely grained stone upon which soft metals leave traces. When rubbed, a process known as "probing," precious metal alloy cleaves to the stone, leaving a stripe. The color of the stripe (which reveals the percentage of its content that is base metal) can then be compared to a stripe of a known grade of standard alloy. Despite its primitiveness, this probing process allowed merchants to examine alloys quickly and with reasonable certainty. Though civilizations were using gold and silver currencies as early as 500 b.c., coins were easily forged or diluted with less valuable metals, such as tin or lead. The invention and popularization of the touchstone ensured that pure gold and silver could become a standard expression of value.

As you can see you must focus on the very essence of the passage to find the main idea and disregard the details.

The red, blues, and the blues final are the main idea. especially the last one sentence


A. demonstrate that science can influence non-scientific progress

no at all. never read this in the passage

B. underline the touchstone`s importance in the history of currency

of course. last sentence in particular

C. explain how the touchstone is able to measure the purity of an alloy

no. we do know if that is gold or fake not the purity. Even if this was true is just a detail NOT the main idea

D. explore the etymology of the word "touchstone"

whatever.................

E. refute a historical misconception

No misconception. The passage only say that is illogical to thnk about X when already Y was a knew process before . A sort of precursor

Hope now is more clear

regards

Thanks a ton Carcass. Always insightful!!!

UPDATED the entire passage for further discussions

QUESTION 1


The text is primarily concerned with showing the ancient origin of modern currency and underlines the touchstone’s importance within this history; therefore, choice (B) is correct. Choice (A) is too broad—the passage is concerned only with currency, not science in general. Conversely, choice (C) is too narrow; the passage talks about the touchstone’s historical importance, not just the science behind it. The passage does not discuss where the word came from, so choice (D) is incorrect. Choice (E) is also wrong because there is no historical misconception that needs to be cleared up.

QUESTION 2


Choice (C) accurately describes the reason for including the details concerning the inclusion of lesser metals in early coins: It takes the details of how the touchstone works and shows why the touchstone was important for trade. The passage does not state how individuals previously tested metals, so choice (A) cannot be true. Choice (B) is also incorrect because the date given in the passage is of the earliest use of coins; it does not talk about the date of the touchstone. The purpose of the sentence is not to give a cultural context because the passage does not identify the cultures involved, so eliminate choice (D). There is no counterargument given, making choice (E) incorrect.

QUESTION 3


Choices (A) and (C) are supported by the phrases this probing process allowed merchants to examine alloys quickly and with reasonable certainty. You know that the certainty referred to is about adulterated coins because the passage later mentions that coins were easily forged or diluted. Choice (B) is incorrect because although the passage does mention standardization, it does not mention specifically that it would be a function of the government.