Getting to the correct answer in CR

When looking through answer choices on Critical Reasoning questions, there is always one correct answer to the question. After all, it wouldn’t be fair if two different answers were both legitimate responses to the query being posed. However, just because the other four answers are incorrect, it doesn’t mean that they aren’t tempting. In fact, there is usually one choice the exam is pointing you towards selecting, even though it isn’t the correct option.

Other examples of the choice involve providing known information on a strengthen/weaken question, or giving an answer choice that seems reasonable but not 100% assured on an inference question. The choices will always seem reasonable, and in many cases, they will be the most popular answer choices selected.

Let’s look at a question that deals with this very topic:

A system-wide county school anti-smoking education program was instituted last year. The program was clearly a success. Last year, the incidence of students smoking on school premises decreased by over 70 percent.

Which of the following, if true, would most seriously weaken the argument in the passage?

(A) The author of this statement is a school system official hoping to generate good publicity for the anti-smoking program.
(B) Most students who smoke stopped smoking on school premises last year continued to smoke when away from school.
(C) Last year, another policy change made it much easier for students to leave and return to school grounds during the school day.
(D) The school system spent more on anti-smoking education programs last year than it did in all previous years.
(E) The amount of time students spent in anti-smoking education programs last year resulted in a reduction of in-class hours devoted to academic subjects

On this Critical Reasoning weaken question, it’s important to note the conclusion and the supporting evidence. The conclusion is the middle sentence (The program was clearly a success) as that is unmistakably the author’s main point in this passage. The evidence is everything else, but especially the last sentence, because a decrease of 70% of student smoking on the premises would seem to support the author’s conclusion. We’re tasked with weakening this conclusion, so we must find evidence that refutes this evidence or otherwise makes the conclusion less likely to occur.

There is one trap answer on this question that a lot of students gravitate towards. I’ll let you reread the choices to see which one you singled out (cue jeopardy music).

The answer choice that most people like is B: students who smoke stopped smoking on school premises last year continued to smoke when away from school. After all, the logic seems sound. If students stopped smoking at school, and we’re trying to weaken the conclusion, then it would follow that students smoking everywhere else (at home, in the street, at the Peach Pit…) would weaken the conclusion. Furthermore, this is new evidence that seems to perfectly solve every element we care about. Many students select B here and move on with nary a thought that they just fell into a trap. (It’s a trap!)

Let’s re-examine the conclusion. The conclusion stated that the program was a success, and the program was defined as a county school anti-smoking education program. This means that the students were being educated in an effort to reduce smoking at school. If incidents of smoking at school decreased by 70%, then the program was a success, regardless of whether the students were smoking elsewhere. Indeed, the goal of the program was to reduce smoking in school, and answer choice B does not weaken that conclusion. It weakens the goal of curbing out smoking altogether, but that is a slightly different conclusion that is beyond the scope of this particular argument.

As such, answer choice B seems like a logical answer, but fails to meet the necessary criteria to be the right response. This means that we need to peruse the other four answer choices to identify the correct choice.

Answer choice A, “the author of this statement is a school system official hoping to generate good publicity for the anti-smoking program”, implies that the author may have a hidden agenda. While this may be true, it doesn’t account for the 70% decrease of on-campus smoking, so it doesn’t do a good job of weakening the argument given the evidence presented. We can eliminate this choice.

Answer choice C, “Last year, another policy change made it much easier for students to leave and return to school grounds during the school day” does indeed weaken this argument. If your only evidence is the decrease in smoking on campus, then any alternative explanation as to why that happened weakens your argument. The students may not be smoking on the grounds anymore, but they are still smoking at school, just a little further away than before. Indeed, the smoking policy may have had absolutely no effect on students’ habits whatsoever, greatly weakening the conclusion.

Answer choice D, “The school system spent more on anti-smoking education programs last year than it did in all previous years” actually somewhat strengthens the argument. If the school system put a lot of money into the program, then it would be more likely to succeed. Even if the school overspent, the success of the program is determined by the students’ smoking habits, not the program’s budget.

Answer choice E, “the amount of time students spent in anti-smoking education programs last year resulted in a reduction of in-class hours devoted to academic subjects” is also somewhat tempting, because it introduces the concept of side-effects. In the real world, we might do something that has unintended consequences, and look back on the decision as a mistake. Side effects don’t affect the success rate of the program, so this answer choice can be eliminated.

As we saw, answer choice C is the correct selection. However, it may not be the most common selection on this exam, as another answer choice was more enticing for a lot of students. The CAT is designed to provide tempting answer choices that almost solve the issue at hand, but fall short in one crucial measure.