Paradox Question!!!

[dv2020]

A survey of alumni of the class of 1960 at Aurora University yielded puzzling results. When asked to indicate their academic rank, half of the respondents reported that they were in the top quarter of the graduating class in 1960.

Which one of the following most helps account for the apparent contradiction above?

(A) A disproportionately large number of high-ranking alumni responded to the survey.
(B) Few, if any, respondents were mistaken about their class rank.
(C) Not all the alumni who were actually in the top quarter responded to the survey.
(D) Almost all of the alumni who graduated in 1960 responded to the survey.
(E) Academic rank at Aurora University was based on a number of considerations in addition to average grades.

[sivaelectric]

My Choice B

[cans]

IMO A

[sivaelectric]

Hi Cans, when you say A does it not contradict the year mentioned. The alumni were supposed to be from 1960 only.

[dv2020]

The OA is indeed A but i feel for this to be the correct AC there need to assumptions within the AC as pointed out by sivaelectric above.
@cans can you throw some light...
thanks

[newton9]

P: Half of the respondents responded that they are in top quarter of their class.

The only way this can be true is if most of the respondents to the survey are high-ranking.

Say there are 100 members and 25 members were surveyed.

If 20 of them responded that they were in top quarter of the class, this means that a higher proportion of the respondents were high-ranking.

A is the answer.

C actually doesn't explain the paradox.

[Frankenstein]

Hi,
Lets say there are 80 students in the class of 1960 and 28 students attended the survey. More than half of them were from top quarter of the class. That means, out of 28, 14 were ranked below 20 of the 80 student class, and the remaining 14 students were from the rank-21 to rank-80 pool. That means the survey group has disproportionately larger number(50%) of high-ranking(rank-1 to rank-20) students. This is disproportionate because, if it were uniform, roughly 7 students should be from top-20 and the remaining 21 from rank-21 to rank-80.

Cheers!

[subhashghosh]

+1 for A.

[cans]

Hi Cans, when you say A does it not contradict the year mentioned. The alumni were supposed to be from 1960 only.

Class of 1960 means that class graduated in 1960. (not that it starts in 1960)
And question mentions that respondents reported that they were in the top quarter of the graduating class in 1960. Thus No contradiction.

[dv2020]

The key here is to read the argument carefully...it says When asked to indicate their academic rank, half of the respondents reported that they were in the top quarter of the graduating class in 1960.

so it is half of the respondents nowhere in the argument it says that all the graduating class was contacted/surveyed

So it was passive/careless reading on my part to miss this one.....

[sivaelectric]

Careless on my side too dv2020 thanks for bringing out that point.