In 1987, an environmental action group reported a 65-percent response

D.
a) even if membership has declined, the argument talks about percentage of responses which is not dependent on membership
b) absolute number of surveys is not relevant as even with smaller or higher number of responses, percentage of responses can be the same or can vary
c) stem does not specify anything about comparison between ocean and air.
e) this cannot be inferred based on the stem.

"On the basis of these results" in the conclusion leads to D.

I think that I have found a key of tackling assumption questions.

As per theory Assumption is an unstated evidence, and that unstated evidence is our answer. So let's put every option in the passage before conclusion and re-read the passage. If you practice the same it will take around one and half minute.

Let's see the same approach for this question.

Prephrase the passage -

65-percent response rate to ocean dumping. On the basis of these results replace this with a word therefore, Therefore, group expects 65-70% for air pollution questionnaire.

my passage becomes -

65-percent response rate to ocean dumping. Therefore, group expects 65-70% for air pollution questionnaire.

let's put all options in the passage

A. 65-percent response rate to ocean dumping. The group’s membership has not declined by more than 5 percent since 1987. Therefore, group expects 65-70% for air pollution questionnaire. -- Out of Scope

B. 65-percent response rate to ocean dumping. The same number of surveys will be distributed as were distributed in 1987. Therefore, group expects 65-70% for air pollution questionnaire. -- Author is least bother about number of surveys.

C. 65-percent response rate to ocean dumping. People who are concerned about ocean dumping are even more concerned about air pollution. Therefore, group expects 65-70% for air pollution questionnaire. - This may work hold on

D. 65-percent response rate to ocean dumping. The response rate of one questionnaire can be predicted from that of another. Therefore, group expects 65-70% for air pollution questionnaire. - Good option Hold on

E. 65-percent response rate to ocean dumping. The total amount of pollution today is the same as it was in 1987. Therefore, group expects 65-70% for air pollution questionnaire. -- we are least bother about this option

Now we have two options in Hand C and D. C is extreme it uses word 'more'. If you are stuck between extreme and mild option go with mild one....90% this option will be right

Therefore, IMO D

Obviously, it is between C and D.
I went ahead with C, because at least as many people are expected to respond to another issue that resonates with them.

Although D is good well. It doesn't do enough justice to greater than 65% part.

In 1987, an environmental action group reported a 65-percent response rate to a questionnaire sent to all of its members. The subject of the questionnaire was ocean dumping. On the basis of these results, the group expects a 65-to-70 percent response rate to its upcoming questionnaire on air pollution.

c) People who are concerned about ocean dumping are even more concerned about air pollution.
d) The response rate of one questionnaire can be predicted from that of another.


By asking few simple questions we can eliminate C.

Is it necessary that only people who are concerned about ocean dumping/air pollution. should respond to the survey.(people may just fill in some junk and give back the questionnaire 10% may really take it serious rest may just fill in junk)

wow...I answered this question long back
Applying the CR bible technique of logical negation, I would pick the answer D though. It seems right because even if people are not so concerned about air pollution, they might respond to the survey (burden of membership I suppose )

But if D is negated, you cannot put forth the argument at all.
OA??

A good way to see the correct answer in assumption questions is negating each answer and see if the reasoning collapses.
a) The group's membership has declined by more than 5 percent since 1987. We are concerned about response rate, not absolute values.
b) The same number of surveys will not be distributed as were distributed in 1987. Same as a), we are concerned about the response rate, not the number of surveys.
c) People who are concerned about ocean dumping are not concerned about air pollution. Anyways they can answer the survey.
d) The response rate of one questionnaire can't be predicted from that of another. Then they should come out with a different expectation. The reasoning becomes faulty here.
e) The total amount of pollution today is not the same as it was in 1987. Again, doesn't affect the response rate.

Premise 1 : In 1987, an environmental action group reported a 65-percent response rate to a questionnaire sent to all of its members.
Premsie 2 : The subject of the questionnaire was ocean dumping.
Conclusion : the group expects a 65-to-70 percent response rate to its upcoming questionnaire on air pollution.

Author is assuming that because in last questionnaire they got 65% response so even this time also they will get 65% to 70% response.

A The group's membership has not declined by more than 5 percent since 1987. -> Even if group's membership is declined total percentage would be 100%, so OUT.

B The same number of surveys will be distributed as were distributed in 1987. -> For finding percentage response we require total. Same number of response does not matter.

C People who are concerned about ocean dumping are even more concerned about air pollution. -> Author's prediction is based on last survey/questionnaire. This could be correct be correct but author's prediction is not based on this assumption

D The response rate of one questionnaire can be predicted from that of another. -> CORRECT
Negation: The response rate of questionnaire CAN NOT be predicted from that of another.
This statement weakens the conclusion and states that from last response you can't predict the response of new survey.
Also this statement is defender which removes the other possibilities.

E The total amount of pollution today is the same as it was in 1987. -> Comparison is not stated so this option is out of scope.

Example :
Shopkeeper : Last year we sold 100 Kg Banana Chips so this year we would sell almost 150 Kg Potato Chips.

Here Shopkeeper does not assume that people like Potato Chips more than Banana Chips. His assumption is based on last year's sell.

Hope above explanation will be useful.

We are only concerned with the %age of the responses. The amount of pollution, the number of people or their beliefs should be irrelevant here.
D is the only choice dealing with that.

I vote for D

A - just because there was large response rate on that topic doesn't guarantee large response on this one
B - number of surveys has nothing to do with the argument
C - if this is true, then we'd be expecting more than 65-70% response
D - Correct - Only answer that ties ocean dumping questionnaire to air pollution questionnaire.
E - We do not have indication of how people felt about pollution in relation to ocean dumping and how people's responses have changed over time

IMO why C is wrong is because it says "People who are concerned about ocean dumping are even more concerned about air pollution." So this means the number of people out of the total population(i.e. response rate) is still the same for air population as for water population and that only their opinion is more strong towards air pollution as opposed to water pollution.

On the other hand if the option said "More People are concerned about ocean dumping than about air pollution." in that case C would have been a correct option to choose. So the correct answer must be D

Consider Kudos please if you like my approach

Yeah, Poorva, You caught the exact reason why option C is wrong. Here People are those who have already responded in the earlier survey so even if they respond it more the percentage will be same.

Here is my view for this CR.

Being concerned about something is different from reporting such concerns through the survey or questionnaire.
In option C, people concerned about ocean dumping might be more concerned about air pollution. But these people are reluctant or not interested to report such concerns via questionnaires.
Or it could be possible that people who are nor concerned with ocean dumping are more concerned with air pollution but they are not approached via questionnaires.
C is wrong.

But yes D is correct for reason mentioned in thread. No need to repeat it.

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