In the summer of 1936 a polling service telephoned 10,000 United State

Question

In the summer of 1936 a polling service telephoned 10,000 United States voters and asked how they planned to vote in the coming presidential election. The survey sample included a variety of respondents—rural and urban, male and female, from every state. The poll predicted that Alfred Landon would soundly defeat Franklin Roosevelt. Nevertheless, Roosevelt won in a landslide.

Which one of the following, if true, best explains why the poll’s prediction was inaccurate?

(A) The interviewers did not reveal their own political affiliation to the respondents.

(B) Only people who would be qualified to vote by election time were interviewed, so the survey sample was not representative of the overall United States population.

(C) The survey sample was representative only of people who could afford telephones at a time when phone ownership was less common than it is today.

(D) No effort was made to determine the respondents’ political affiliations.

(E) Because the poll asked only for respondents’ candidate preference, it collected no information concerning their reasons for favoring Landon or Roosevelt.

Bunuel · Accepted Answer

OFFICIAL EXPLANATION

(A) No. This would increase the poll’s credibility. Had the interviewers revealed their political affiliations, it would have decreased the poll’s credibility because their opinions might have influenced the people they were interviewing.

(B) No. This would increase the poll’s credibility. The opinions of those unqualified to vote were irrelevant since they did not vote.

(C) Yes.  We are looking for something that might have caused the poll to be unrepresentative of the general population. Now, in 1936, phones were not as common as today. If most of the phones were in the homes of the wealthy who held opinions that differed from those of most of the population, then the poll would not have been based on a good cross section of the electorate.

(D) No. Asking for the respondents’ political affiliations would probably help determine how representative the poll was. However, if a disproportionate number of respondents were supporters of Alfred Landon, this choice does not explain why the selection process was skewed.

(E) No. This might somewhat explain the inaccuracy of the poll: Perhaps the support for Landon was weak or very volatile. Nevertheless, there is a much stronger explanation offered.

ImJun · Answer

(B) Only people who would be qualified to vote by election time were interviewed, so the survey sample was not representative of the overall United States population.
It makes a bit of sense, but not strongly clear enough to explain the shocking result of the election.

(C) totally explains it, since the fewer people with telephones at home, the less accuate the telephone survey will be.

tryingharder · Answer

The argument is least bothered about overall United States Population. The Argument has explicitly talked about United States voters. As maintained by the argument it is clear that  United States Voters are NOT an accurate reflection of the the GENERAL POPULATION.  Therefore no need to assume something that is long way away. 
B can be ruled out in view of the reason that the information in B is beyond the facts stated on the argument.

C is precise

dwivedys · Answer

If as B says only those people who were eligible to vote were interviewed - the survey was in fact representative of the population. B just stitches two contradistinct scenarios - if eligible voters alone were interviewed - how can the sample not be representative? You don't want to count the opinion of those who would not have been eligible to vote in the first place So B does not explain the discrepancy.

Desertchampion · Answer

In this question, we're looking for a discrepancy between the predicted outcome and the actual outcome of the election. The answer choice should give us a reason for this discrepancy.

(A) The interviewers did not reveal their own political affiliation to the respondents.
 If the interviewer HAD REVEALED their own political affiliation, it may have altered the answers they received, however this says that they did not reveal their own political affiliation, so it should have not had any effect on the results of the survey.

(B) Only people who would be qualified to vote by election time were interviewed, so the survey sample was not representative of the overall United States population.
 Again, if the opposite of this had happened, it would have had an effect on the survey results, but it didn't and therefore it should have not had any effect on the survey results.

(C) The survey sample was representative only of people who could afford telephones at a time when phone ownership was less common than it is today.
 Bingo! This shows that there may be a reason as to why only some people in the population were excluded from the survey.

(D) No effort was made to determine the respondents’ political affiliations.
 This is irrelevant. Even if respondents were asked about their political affiliations, it would not have had an effect on the outcome of the survey results.

(E) Because the poll asked only for respondents’ candidate preference, it collected no information concerning their reasons for favoring Landon or Roosevelt.
 Again this is irrelevant. Even if the poll collected the reasons for favoring Landon or Roosevelt, it would not have had an effect on the survey results.

The correct answer is answer choice C.

Please give kudos if this was helpful in any way!

gloomybison · Answer

I believe that this question is seriously flawed;

We know that 10k people were surveyed from different places/genders, and we are looking for a bias in the survey to conclude that the survey results didn't show the reality.

(C) The survey sample was representative only of people who could afford telephones at a time when phone ownership was less common than it is today.

How can someone's affording a telephone in 1936 may create a bias? Can you safely assume that they are rich?even if you assume so, does being rich create some sort of tendency to vote for someone? This option stands on a few links of further assumptions, making it quite a feeble and shaky of an answer...

VerbalBot · Answer

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In the summer of 1936 a polling service telephoned 10,000 United State

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In the summer of 1936 a polling service telephoned 10,000 United State

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