Note that the argument concerns "response rates". Response rates are percentages, so absolute numbers should not have anything to do with the correct answer. Think of it this way: out of 100 people, if 70 answer, then you have a 70% response rate. If you send out 1000 forms and 650 people answer, then you have a 65% response rate. Even though in the first example you have a higher response rate, it's clear that the second example garnered the most physical answers.

So, based on this reasoning, we can safely eliminate answer choices A and B.

C may be true, but that doesn't predict their willingness to answer questionnaires. We're focused on response rates, not "caring".

D is the best, IMHO. This is an underlying assumption of the argument. If you deny this assumption, then the argument falls apart. If you could not make predictions based on past events, then there's no basis for the claim that the response rate will be 65 to 70 percent.

E - it's irrelevant to the point of response rates. Maybe the respondents are not even aware of this (although it's unlikely).

gmatnmein2010 wrote: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.

The environmental group's expectation is based on which of the following assumptions?

a) The group's membership has not declined by more than 5 percent since 1987.
b) The same number of surveys will be distributed as were distributed in 1987.
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.
e) The total amount of pollution today is the same as it was in 1987.

Conclusion: the group expects a 65-to-70 percent response rate to its upcoming questionnaire on air pollution.
Assumption: The response rate for the survey on Air Pollution will be similar or slightly more than that of the survey on Ocean Dumping

a) Irrelevant
b) Irrelevant
c) Hold - A strong candidate
d) Hold - It could be
e) Irrelevant

Between C and D; I would choose D [it talks about response rate]

I also chose D because in totality this is the assumption. C could be misleading but wasn't compelling enough for me

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.

The environmental group's expectation is based on which of the following assumptions?

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 bothered 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 bothered 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

(D) wins