Hey there,
Psychological Studies have found that children who are afflicted with Attention Deficit Disorder (ADD) are difficult to teach, inattentive, and unable to sit still for very long.
A. that children who are afflicted with Attention Deficit Disorder (ADD) are difficult to teach, inattentive
B. that children who are afflicted with Attention Deficit Disorder (ADD) are difficult to teach, inattentive, and are
C. children who are afflicted with Attention Deficit Disorder (ADD) are difficult to teach, inattentive, and they are
D. children who are afflicted with Attention Deficit Disorder (ADD) are difficult to teach, and inattentive, and they are
E. that children who are afflicted with Attention Deficit Disorder (ADD) are difficult to teach, they are inattentive, and are
The first thing I'd look at here is the split between the beginnings of the answer choices. (A), (B), and (E) begin with "that children," whereas (C) and (D) simply start in with "children." Here's why we can eliminate (C) and (D) based on that distinction:
Our setup is the verb "found," and what do you find, always? Nouns. You find nouns. For instance, you find
your other shoe or you find
a secret passageway. The verb "found" is transitive (with the rather obscure exception of its trial-related intransitive meaning -- "We find for the defendant," e.g.) and as such, always waits for an object to come follow it. "Children ... are difficult to teach," taken alone, is a complete independent clause, i.e. an entire sentence of fact, not a noun. But by inserting the conjunction "that" before it, we create instead a noun phrase ("that children ... are difficult to teach"). And as a noun phrase -- a
thing that can be found -- it delivers what "found" is waiting for. [Note: this discussion applies to many, many verbs other than "found."
Whenever you have a setup that's a verb that requires an object, you need to make sure in a similar fashion that what you're following it with can function as an object. So, for example, I'd need the "that"s in all of these phrases; none of them would stand up otherwise: "We discovered that he was lying," "She liked that he always did the dishes," "I've learned that you are an Olympian," "I hate that you're always late."]
So, we're down to A, B, and E.
At this point we look at the differences in the ends of the answer choices. (A) is faithful to rules of parallelism -- "difficult," "inattentive," and "unable" are all adjectives. (B) does not behave so well:
difficult to teach, inattentive, and are unable
That "are" before "unable" messes up the parallelism. (E) is likewise messy:
difficult to teach, they are inattentive, and are unable
While we might be able to make a (shaky) argument for the presence of the "are" here, since at least it's consistent in this option, we have no grounds on which to justify the presence of the "they." That "they" messes up the parallelism.
So this question tests two good grammar issues, and also accommodates nicely the "look for splits at the beginning -- rule out two; look for splits at the end -- rule out two more" strategy!
Cheers,
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