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Critical Reasoning: Investigation Questions

A cellular communication development facility was built just outside the town of Qwertyville. Five years later almost 28% of the population have experienced cases of abnormal cell growth. Recently, a cellular company has applied to the town council of Iopville for an approval to build a development facility there. The Iopville council should not allow the building of such a facility on its outskirts since its population would suffer like that of Qwertyville. 

Which of the following would be most useful to establish in order to evaluate the argument above?



This answer choice introduces a factor that is out of the scope of the argument. The health problem discussed is abnormal cell growth so additional disorders are irrelevant.



Answering the question in this answer choice would not help us determine whether the Iopville council should approve or disapprove the new facility. Using the same water supply as the homes can't really effect anything since the water is entering, not exiting, the facility.



This answer choice is irrelevant to the argument's conclusion and cannot, therefore, determine its validity. The causes of abnormal cell growth under question are cellular communication development facilities, not cellular phones.



This answer choice presents a question that, even if answered, can in no way affect the argument's conclusion. It doesn't matter what the population knows; the author makes a recommendation that is aimed at the Iopville council.

Nice work!


The author makes a recommendation based on a suggested relationship. However, this relationship between the facility and the abnormal cell growth is not supported since 28% could be much higher or much lower than the standard rate of abnormal cell growth.

The Qwertyville percentage must be compared to an average or control figure, in order to support or weaken the recommendation. If the figure of 28% proves similar to such an average, or lower, the conclusion is invalidated. If it's much higher, the recommendation should probably be taken seriously.

Whether the tests administered to the residents of Qwertyville check for abnormal cell growth alone or for additional disorders
Whether the cellular development facility built outside Qwertyville uses the same water supply as the town's residents
Whether the percentage of abnormal cell growth cases in Qwertyville is higher than that of other towns without such development facilities nearby
Whether a direct relationship between using a cellular phone and abnormal cell growth has been established based on adequate research
Whether the population of Iopville is as involved in current town activities as that of Qwertyville