Citing the fact that the real gross domestic product (GDP) per capita was higher in 1997 than ever before, some journalists have argued that the United States economy performed ideally in 1997. However, the real GDP is almost always higher than ever before; it falls only during recessions. One point these journalists overlooked is that in 1997, as in the twenty-four years immediately preceding it, the real GDP per capita grew nearly one-half percent a year more slowly than it had on average between 1873 and 1973. Were the 1997 economy as robust as claimed, the growth rate of real GDP per capita in 1997 would have surpassed the average growth rate of real GDP per capita between 1873 and 1973 because over fifty percent of the population worked for wages in 1997 whereas only forty percent worked for wages between 1873 and 1973. If the growth rate of labor productivity (output per hour of goods and services) in 1997 had equaled its average growth rate between 1873 and 1973 of more than two percent, then, given the proportionately larger workforce that existed in 1997, real GDP per capita in 1997 would have been higher than it actually was, since output is a major factor in GDP. However, because labor productivity grew by only one percent in 1997, real GDP per capita grew more slowly in 1997 than it had on average between 1873 and 1973.

1. The passage is primarily concerned with
A. comparing various measures used to assess the performance of the United States economy in 1997
B. providing evidence that the performance of the United States economy in 1997 was similar to its performance between 1873 and 1973
C. evaluating an argument concerning the performance of the United States economy in1997
D. examining the consequences of a popular misconception about the performance of the United States economy in 1997
E. supporting an assertion made by journalists about the performance of the United States economy in 1997

OA:C

when you review main-idea questions, you should always think (in general terms) about how the passage would look for each answer choice.

choice C says
evaluating an argument concerning xxxx

in general, this means...
 the passage should start with the 'argument' (perhaps after a short introduction, perhaps not),
 then the author should JUDGE the argument. (this is what 'evaluate' means. is it good? is it bad? is it likely to be correct/incorrect/likely/unlikely? always, sometimes, or never? and so on)
 ...and, of course, the REASONS for that judgment.

that's exactly what happens in this passage.

choice D says
examining the consequences of a popular misconception

if this were the correct choice, the author would...

I)state something wrong that lots of people believe
you can already kill choice D at this point, without even reading past the word 'popular'. the author only talks about what 'some journalists' have said.

AND THEN
II)talk about what has happened because lots of people believe that thing. ('consequences')
this doesn't happen here either.

2. According to the passage, which of the following is true of the average rate at which real GDP per capita grew in the twenty-four years immediately before 1997?
A. It was less than it had been between 1873 and 1973 because only forty percent of the population worked for wages between 1873 and 1973.
B. It was less than it had been between 1873 and 1973 because labor productivity grew less between 1973 and 1997 than it had between 1873 and 1973.
C. It was less than it had been between 1873 and 1973 as a result of an increase in the percentage of the population earning wages during these years.
D. It was less than the average rate at which real GDP per capita grew between 1873 and 1973.
E. It was less than the rate at which real GDP per capita grew in 1997.

OA:D

A is incorrect because it's nonsense.
'only 40 percent of the population worked for wages between 1873-1973' --> from this, we would expect gdp growth to have been SLOWER during that period. 
(the author points this out... but it's also common sense.)

so, A is like saying "I weigh less than my friend BECAUSE he only eats half as much food as i do." huh?

B is unjustified because the passage says nothing, ever, about the growth of labor productivity between 1973-1997.
there's some discussion of the figure for 1997, but nothing about that whole period.

alsoyou can eliminate A and B without looking at the passage at all. in fact, you can eliminate them even if the passage has been stolen from you.

you can eliminate A and B here simply because there can only be one correct answer!

consider:

A)X happened because Y.

B)X happened because Z.

D)X happened.

if only one of these statements is true, then it ABSOLUTELY MUST be choice D.
you can see why: if either A or B were true, then D would have to be true as well!

there's never more than one correct answer.
so, as soon as you notice choice D, you can eliminate A and B without even looking at the text.

3. It can be inferred from the passage that which of the following is the reason that the author faults the journalists referred to in highlight text(some journalistshave argued )?
A. They believe that the real GDP per capita in 1997 was higher than the real GDP per capita had ever been before.
B. They argue that the rate at which real GDP per capita grew in 1997 was faster than the average rate at which it had grown between 1873 and 1973.
C. They overestimate the effect of labor productivity on the real GDP per capita in 1997.
D. They overestimate the amount by which real GDP per capita in 1997 surpassed real GDP per capita in earlier years.
E. They fail to consider the real GDP per capita in 1997 within an appropriate historical context.

OA:E

first, just to make sure this is clear, "they" in this answer choice refers to the journalists, not to the author of the passage. (the author of the passage is singular -- note that it's not "authors" -- so the pronoun "they" cannot refer to the author of the passage.)

the passage states that the journalists failed to consider this fact -- i.e., the implication is that the journalists didn't make ANY sort of comparison between the 1997 rate and the 1873-1973 average (the latter of which is the "appropriate historical context" mentioned in the correct answer choice). there is definitely no evidence from which to claim that the journalists make the claim posited in choice (b) -- a claim that contradicts the factual information that you underlined (passage says "half as fast"; choice b says "faster").

also, beware of picking answer choices that contain almost exactly the same words that appear in the original passage, as this one does.
unless the question starts with "According to the passage" or "The passage indicates", DO NOT pick an answer choice whose wording is almost identical to the wording of the passage itself, unless you are absolutely, 100%, do-or-die sure that it is correct; that is perhaps the most common type of "trap" answer on all of RC.

4. The author of the passage asserts that "the real GDP is almost always higher than ever before" (see highlighted text) most probably in order to(the real GDP is almost always higher than ever before)
A. show that a fact cited in support of a claim is inaccurate
B. show that a fact cited in support of a claim actually contradicts the claim
C. show that a fact cited in support of a claim does not prove the claim
D. explain why a fact cited in support of a claim is relevant to the claim
E. explain how the proponent of a claim selected a fact cited in support of the claim

OA:C

choice B says 'contradict'. nothing is contradicting anything herei.e., the cited statement certainly does not DISprove (= 'contradict') the claim.
so choice B is wrong.

...then B must be wrongeven if we don't have the text of the passage.

remember, there can be only ONE correct answer.

'contradicts' is MUCH stronger than 'does not prove'.
i.e.,
...if something 'contradicts' X, then, of course, it does not prove X.
...but not the other way around (there are plenty of things that 'do not prove' X, but don't contradict it either.)

e.g.,
Yesterday was Thursday.
This DISPROVES that 'today is Sunday.'

Yesterday was Thursday.
The sun is shining.
My name is Ron.
Each of these things FAILS TO PROVE that 'today is Sunday.'

i think you see my point: if B were true, then C would have to be true as well. thus B cannot be the correct answer.

in other words, we have the same situation as this:

Blah blah blah xxxx [math statements] xxxx xxxx blah blah. Therefore we know that
(A) x is greater than 2.
(B) x is greater than 4.
(C) y is less than 2.
(D) y is less than 4.

here, it's impossible for B or C to be the correct answer. see if you understand why.