CAT Critical Reasoning Practice question with Solution 89

The professor’s argument makes the “assumption of representativeness” without justifying it. She argues that college students in general don’t write as well as they used to; her evidence is that almost all of her students’ papers were poorly written. She assumes without evidence that the writing produced by her students is representative of the writing produced by college students in general. But, it needn’t be.

(B) and (C) While it’s true that no proof of the professor’s competence is offered, this is a much less important omission than that mentioned in (A). If we were given the “proof” that (B) mentions, would the prof’s conclusion be stronger? No, because (A)’s crucial assumption would still be unsupported. So (B) is far from the biggest flaw. As for her teaching skills, we don’t even know she teaches writing, so we can’t argue, as (C) does, that she is responsible for her students’ poor abilities.

(D) There is no contrary evidence. If contrary evidence were presented, we could expect the author to address it. We can’t, however, fault her for not presenting evidence against herself.

(E) While it’s true that writing well and writing poorly may be somewhat subjective terms, they definitely aren’t ambiguous. Moreover, the term “ungrammatical” certainly isn’t ambiguous. However, even if you did consider some of the terms to be in need of further definition, this clearly isn’t as serious a weakness as that described in answer choice (A).