The government has made great strides in implementing immunization in public school systems despite its cost. When all children are properly immunized, we will be able to ensure their health.
Which of the following identifies an assumption in the author's argument?
Only public schools require immunization.
Children are not already properly immunized.
If not immunized, most children will fall victim to disease.
Immunization is effective enough to justify its cost to the taxpayer.
Immunization is the only precaution necessary to guarantee a child's health.
I liked this question and want to see the reasons why you all think the choices are wrong or right.
"Ensuring kids' health" is a pretty broad and ambitious agenda, but the author says that it's a reachable goal if all kids are properly immunized. He must be assuming that nothing else is needed to achieve the goal, and that makes (E) right.
The possibility that other institutions (A) and, inferably, other populations, might need to be immunized falls outside of the scope, which deals with the health of kids only.
(B), while tempting, is not something the author is counting on to be true; if, contrary to (B), the author were to learn that all kids are immunized, he'd simply say "Great! So their health is ensured." (This use of the Kaplan Denial Test—a concept we'll take up in the Challenge Workshop—demonstrates that (B) is not a necessary assumption.)
(C) represents a common logical flaw. Yes, the author believes that immunization will ensure kids' health. That doesn't mean that lack of immunization will lead all to disease vulnerability.
(D), meanwhile, goes way outside the scope in bringing in the cost issue, which is only a side note, not a major part of the logic.