CAT Critical Reasoning Practice question with Solution 42

According to the last sentence, if the human auditory system is an imperfect receptor of sounds then it is impossible for every possible permutation of a spoken language’s basic language sounds to be an understandable word. But the previous sentence said that if a spoken language is completely efficient, then it must be true that every permutation of its basic language sounds can be an understandable word. When we combine those two thoughts we get (E): if the human auditory system is an imperfect receptor, then not every permutation of its basic language sounds is an understandable word. This triggers the contrapositive of the second sentence, allowing us to conclude that no language is completely efficient.

(A) The stimulus gave no grounds for associating efficiency with usefulness or redundancy with reliability; instead, the stimulus said that together efficiency and redundancy could help bring about both usefulness and reliability.

(B) The stimulus never said whether or not redundancy is possible in a spoken language; in fact, the stimulus never mentioned redundancy after the first sentence.

(C) The stimulus never even explained what “redundancy” in a language means; certainly we have no idea whether “complete redundancy” rules out usefulness in a language.

(D) assumes that the imperfection of the human auditory system is the only obstacle preventing every permutation of language sounds from being an understandable word. The stimulus, however, merely said that this imperfection was an obstacle, not that it was the only obstacle.