PrepTest 115, Section 4, Question 4
Among North American school-age children, there is a(26 more words not shown)
The argument requires the assumption(1 more words not shown)
- Aa sedentary lifestyle(9 more words not shown)
- Bobesity among North(10 more words not shown)
- Cgenetics makes no(4 more words not shown)
- DNorth American school-age(12 more words not shown)
- Ewithin a decade(10 more words not shown)
Reading the argument
Children who watch more television are more likely to be obese. Why? Watching television might contribute, but the association alone doesn't settle the cause. Perhaps something else about the children's routines leads both to more television and to less exercise.
Then the author introduces interactive television. Is that the same kind of activity? What if interacting with the program requires moving around? We haven't been told that this new form of television has the same effects as the television in the evidence.
What we’re looking for
For a required-assumption question, I'd look for something the author needs in order to get past those concerns. Perhaps the argument needs a connection between viewing and obesity, or a reason the new kind of viewing will have a similar effect. We want a claim the reasoning depends on, rather than a claim that would merely make it sound more convincing.
Working the answers
- A
The argument doesn't need a sedentary lifestyle to rank among the most important causes. Diet or other factors could play a larger role while an increase in television viewing still made some contribution. Also, this broad claim doesn't tell us what interactive television changes about children's behavior.
- B
We don't need this historical parallel with cable television. The author could be right about interactive television even if obesity didn't rise when cable became available. Cable viewing and interactive viewing could develop differently, and the argument never bases its forecast on a cable-television example.
- C
More than one factor can contribute. Genetics could make a significant contribution while television habits also matter. The forecast doesn't require television to be the only influence on obesity, so eliminating a genetic contribution is unnecessary.
- DCorrect
Here is another missing step: why would introducing interactive television mean more television viewing? The evidence links the amount watched with obesity. To use that relationship as the basis for an increase in obesity, the author is taking for granted that the amount watched will increase.
Suppose children simply replace an hour of ordinary television with an hour of interactive television. Their viewing time hasn't increased. The relationship cited in the premise would then give us no reason to predict the increase in obesity.
D supplies that needed change in viewing time. It doesn't resolve every concern we raised about causation or about what interactive viewing involves. A required assumption can be one necessary part of the argument without making the entire argument convincing.
- E
Almost universal availability within a decade isn't required. The forecast concerns North American school-age children, and increased viewing among enough of those children could matter even if the technology never became universally available. The author also gives no ten-year deadline.
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