In an experiment, one thousand nine-year-old children were allowed to choose whether to participate in a program in which the researchers taught them dance during the daily break from their lessons. Four hundred of the children chose to participate for at least one year. At the end of the year, researchers found that the children who had participated had significantly better balance, on average, than those who had not. The researchers hypothesized that dancing resulted in a sustained improvement in the children's sense of balance.

It would be most helpful in evaluating the researcher's hypothesis to know whether the researchers (1) prior to having (2)

Select Researchers for the phrase that fills the blank labeled 1 in the given statement, and select Prior to for the phrase that fills the blank labeled 2 in the given statement to create the most accurate statement on the basis of the information provided. Make only two selections, one in each column.

[quote="goodyear2013"]In an experiment, one thousand nine-year-old children were allowed to choose whether to participate in a program in which the researchers taught
them dance during the daily break from their lessons. Four hundred of the children chose to participate for at least one year. At the end of the year,
researchers found that the children who had participated had significantly better balance, on average, than those who had not.
The researchers hypothesized that dancing resulted in a sustained improvement in the children's sense of balance.

It would be most helpful in evaluating the researcher's hypothesis to know whether the researchers ___1___ prior to having __2__.

Select Researchers for the phrase that fills the blank labeled 1 in the given statement, and select Prior to for the phrase that fills the blank labeled 2 in the given statement to create the most accurate statement on the basis of the information provided. Make only two selections, one in each column.

1:Researchers | 2: Prior to
0 0 tested the children's ability to dance
0 0 designed a second experiment
0 0 divided the children into the two experimental groups
0 0 tested the children's sense of balance
0 0 taught dance to the children through the dance program

Hi, I found this question hard. In fact, not sure where to start with.
Can anyone explain this for me, please.

Hi goodyear2013
The passage says that, researchers "taught dance to childerne" and after one year they concluded that the children who had participated had significantly better balance, on average, than those who had not. And thus Dancing helped
Now as the result is based on the "average", if some of the children who took the program already knew dancing then the resulted average would stand incorrect.
Therefore Ans :
the researchers ___1.tested the children's ability to dance___ prior to having __2.taught dance to the children through the dance program__.

Hope it helps.

IMO, C is incorrect because, it implies that comparing the two groups is still the best way to conclude whether the dance lessons led to an improvement. However, this is not the best method, as it may be the case that students who took lessons (group A) did not improve, but those in the other group (group B) declined in their ability. Or, it may be that group A declined in their ability, but it was still far better to begin with. E is a good choice, because it directly determines whether dance lessons led to an improvement by only focusing on group A.
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gmat800live, I don't mind weighing in on this one... except that I'm not 100% sure that it's an official question. If it isn't, I don't think it's going to be worth anybody's time. Do you happen to know the source of the question? goodyear2013 posted this in 2014, so s/he might have stopped monitoring this thread a long time ago.
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