Bunuel wrote:

Attention Deficit Disorder (ADD) is a condition characterized by an inability to focus on any topic for a prolonged period of time, and is especially common among children five to ten years old. A recent study has shown that 85 percent of seven-year-old children with ADD watch, on average, more than five hours of television a day. It is therefore very likely that Ed, age seven, has ADD, since he watches roughly six hours of television a day.

The argument above is flawed because it

(A) cites as a direct causal mechanism a factor that may only be a partial cause of the condition in question

(B) fails to indicate the chances of having ADD among seven-year-old children who watch more than five hours of television a day

(C) limits the description of the symptoms of ADD to an inability to focus for a prolonged period of time

(D) fails to consider the possibility that Ed may be among the 15 percent of children who do not watch more than five hours of television a day

(E) does not allow for other causes of ADD besides television watching

KAPLAN OFFICIAL EXPLANATION:

The author's conclusion pops up at the end, where she states that Ed is likely to have ADD because he watches television a lot and is seven. The key piece of evidence is the recent study cited by the author that states that 85% of seven-year-olds with ADD watch more than five hours of television per day. The study thus discusses only the television-watching habits of seven-year-olds who have ADD. The author's conclusion is flawed because it makes a conclusion about a seven-year-old television watcher based on a study about sevenyear-old television watchers with ADD. In other words, there's a scope shift between the evidence and the conclusion. The author errs in accepting the survey as relevant to Ed. (B) expresses this flaw most clearly: In order to make conclusions about Ed and whether he might have ADD, the author must come up with evidence that pertains to Ed, since the original evidence does not. She needs a statistic that states the likelihood that a seven-year-old who watches more than five hours of TV a day would have ADD. The evidence provided sounds like that, but isn't, and (B) captures the gist of the author's mistake. (B) wins.

(A) is confusing, but the argument isn't really about degrees of causation. The author doesn't suggest that age and television-watching cause a child to contract ADD, but that those factors generally appear with the disorder. (A) distorts the author's conclusion by suggesting that it says that Ed's television-watching has caused him to contract ADD, but the author never suggests this.

(C) Yes, the description of ADD symptoms is limited in the manner cited in (C), but that's not a problem. Perhaps some doctors might disagree with the author's definition, but its validity is not the issue at the heart of this argument. Rather, the argument's concerned with Ed's chances of having ADD based on a particular study.

(D) directly contradicts the stimulus, where we learn that Ed does actually watch more than five hours of television per day You may have also noticed that the 15% figure is bogus—it's derived from the 85% figure in the stimulus, but that figure refers to the percentage of children with ADD who watch more than five hours of TV a day. Inferably, we can therefore say that 15% of children with ADD do not watch more than five hours of TV a day, but we can't turn this into 15% of children in general who don't watch more than five hours, as (D) attempts to do.

(E) again distorts the argument, which never suggests that television watching causes ADD. Since no causality is mentioned, we can only assume that the data represents a correlation.

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