To me this question, as with most GMAT CR involving numbers, is less about math, and more about logic.
This is an "Evaluate CR" so what do we know about this question type?
-The CONCLUSION is the most important thing
-The correct answer will be extremely relevant to the conclusion
-Incorrect answer choices will focus on the premise/evidence and be tangential to the conclusion
-Incorrect answer choices may be out of scope/irrelevant
-Depending on the ANSWER to the correct question, the Conclusion should be either strongly strengthened or strongly weakened
Now let's examine just the conclusion:
George Orwell's book 1984 has exercised much influence on a great number of this newspaper's readers.
The claim here is that the book has had "much" influence on a "great" number of readers.
How much is "much"?
How many is "great"?
Not such a strong conclusion.
In order to evaluate whether this is true, we must get information that relates STRONGLY to these ideas of "MUCH influence/GREAT number." Basically, the scope here is the IMPACT 1 book has had.
Prediction: Something that shows whether this 1 book had a BIG impact.
Let's go through and assign "+," "-," and "?" symbols to each answer choice based on whether we believe it shows the book has had a BIG/LITTLE impact.
A. - ("number of book" has no connection to the impact of 1 book in particular)
B. + (choosing between 1984 and other books DOES show its significance to people)
C. - (the conclusion is ONLY interested in the readers; this choice is out of scope)
D. - (again, the conclusion is ONLY interested in this 1 book in particular and its impact)
E. ? (this is a stretch, since we would have to correlate reading with influence)
The "final two" are B and E. Let's look and see how our answer would affect the conclusion.
B. What is 998 people chose The Bible, and 1 person chose 1984, and 1 person chose another book? This would strongly weaken.
What if 500 people chose The Bible, and 498 people chose 1984, and 2 people chose another book? Now there is some potential strength to the conclusion. It doesn't "prove" it, but this is not a CR Strengthen question! Since the answer to this question CHANGES our opinion on the conclusion it is relevant, and therefore useful information to help us "evaluate"!
E. What if 0 people surveyed actually read the books? Isn't it possible a book that we haven't read can influence us greatly? What if we listened to 1984 as a book on tape? What if a friend read it to us? What if we only read critical essays regarding the book, and those essays can a profound impact on us? Just because we don't "read" a book, doesn't mean it automatically would destroy this conclusion.
What if EVERYONE who was surveyed actually read the books they chose. Without knowing the breakdown of HOW MANY actually chose 1984, we cannot anticipate what effect this would have on the conclusion.
The correct answer is
B, because depending on how we answer the question, it has the BIGGEST impact on the Conclusion.
