Variance Test is probably the most helpful tool to figure out the correct answer choice to “Evaluate the Argument” type questions.
We are looking for a question in the answer choices that – depending on the answer to the question – helps identify whether parents in Western countries harm their children by giving them pills to handle simple diseases.
Stimulus: In Western countries parents give their children a pill to overcome the flue. However, pills prevent their immune system to fully develop. Not fully developed immune system hardly can withstand against such lethal diseases as Ebola, smallpox or the Dengue virus. So actually parents harm their children.
Indeed humanity still doesn’t have any effective proven vaccine or medication against such viral disease as Ebola. Maybe the reason is that this virus frequently outbreaks only in poor African countries. Western countries fortunately free of such cases. We know that different climate, geography or hygiene related conditions in different countries will result in different viral diseases. If country A doesn’t suffer from a particular disease X from which B suffers, and if they don’t border, then it is logical that people in country A would rather worry about flue instead of X. The similar scenario repeats in our question. If Western countries don’t suffer from such viral diseases as Ebola, smallpox or the Dengue virus, then they would rather worry about the flu they have.
Let’s begin with the correct answer choice because analyzing it with the Variance Test will display why the other choices are wrong.
C. Whether the lethal viral diseases mentioned are found in Western countries.
YES. If such viral diseases are found in Western countries than the conclusion of the author indeed holds true. Correspondingly, people giving pills to their children to cope less serious disease as the flu may later jeopardise the health of their children.
NOT. As we have already discussed above, in this case there is no place for worry. They would rather worry about the flu. Thus C is correct.
A. What the most common pills against viral illnesses such as the flu are.
Knowing common pills will hardly help us identify whether author’s conclusion is true or not. The stimulus already says that pills given against flu deteriorate the immune system, regardless of their commonness or rareness. What we need to identify whether children actually get those lethal diseases.
B. Whether the infant mortality rates for children in the West are higher now relative to what they were in the past.
YES. If children mortality rate is high, then can we safely conclude that there is some connection between this rate and giving pills to children? Do Ebola, smallpox or the Dengue virus cause this high rate? Not sure.
NOT. The same situation as above. We cannot figure out the reason of this rate just from the information given in this answer choice. Thus B is out.
D. What percentage of parents in Western countries actually give their children pills.
100%. If all parents give pills to their children, does that fact necessarily mean that children will definitely get Ebola, smallpox or the Dengue virus? Not, we can’t safely infer this because such diseases may be absent in the West.
10% the same situation as above. We don’t know the way how children may contact the biruses.
E. Whether new pills will be developed that will both defeat simple illnesses and aid the development of the immune system.
This answer choice is a trap, because it may seem to be answering our question. However, the stimulus discusses the effect of the current pills parents have. Therefore, hypothetical answer choices about future are not relevant to evaluate the argument.
Hence
C