Critical Reasoning - Know the gimmicks to get right answers.

There are gimmicks that show up consistently in GMAT critical reasoning questions. If you familiarize yourself with the gimmicks, then you become more like an insider, someone who knows how the game is created, and so you put yourself in a better position to win the game.

Here's a CR question that incorporates five commonly used gimmicks.

Researchers are using a new method to show that genes cause certain diseases. A group of volunteer subjects is recruited from the group of people determined by physicians to be experiencing a particular health issue. The DNA of the volunteer subjects is then analyzed, and if a certain gene shows up in their DNA with greater frequency than in the DNA of people in the general population, and the difference in frequencies can be shown to be statistically significant, then the researchers conclude that the health issue must be caused by that gene.

Which of the following is an assumption upon which the researchers' conclusions depend?

(A) Unlike some who are paid subjects, volunteers will not falsely claim that they are experiencing a particular health issue in order to be involved in research.

(B) It is not common for many members of an extended family to volunteer to be subjects of research into a health issue that many of the members of the family have experienced.

(C) Determining whether genes actually cause health problems can be a useful step in solving those health problems.

(D) Most people in the general population will remain healthy even after the study is completed.

(E) If genes do cause disease and if this research methodology is used repeatedly, then genetic causes of diseases will be found.

The correct answer is B.

Explanation: The researchers are assuming that the genes are more common in the DNA of the volunteers because the genes are related to a particular health issue, not because many members of extended families, people who are likely to have similar genes, are among the volunteer subjects.

Now, here are the gimmicks, ones like those that you can expect to see regularly used in creating CR answer choices.

(A) The gimmick in this one involves bringing up something that seems relevant but is rendered irrelevant by a specific thing said in the prompt. If you miss a key detail in a prompt, you might pick this type of choice. The key detail in this case is the prompt's saying that physicians rather than the volunteers determine which people are experiencing the health issues. So, that people may claim to have health issues when they don't is irrelevant.

(B) The gimmick used here is the sounds too weird and unrelated to be the right answer gimmick. Most of the other answer choices seem related to research and genes, but this one suddenly focuses on families of the volunteers. To get CR questions right, you have to be careful to not eliminate answer choices just because they initially sound weird or unrelated to the argument. Often the most offbeat sounding answer is the OA.

(C) This answer choice uses a scope gimmick. The GMAT will give you answers that sound relevant or mention something that the test taker is likely thinking. They are, however, beyond the scope of the specific conclusion being discussed. The very specific conclusion being discussed in this case is only that the research connects genes with disease. In the real world, people doing such research may be assuming that it will prove useful, but on the GMAT often such an assumption is not considered within the scope of the discussion.

(D) This one uses a going way overboard while seeming to discuss something relevant gimmick. Yes, the researchers are assuming that the health the general population is somehow different from the health of the volunteer group, but to say that the people in the general population will "remain healthy" is going way too far. The researchers are assuming that most of the people in the general population will never experience any health issue?

(E) This one uses a conclusion that sounds like an assumption gimmick. What better way to get someone to choose the wrong answer to an assumption question than to provide an answer choice that seems to be supported by what is said in the prompt. Anyone looking for an answer choice that "sounds right" might get smoked by a conclusion that sounds like an assumption gimmick.

The more you carefully look at GMAT critical reasoning questions, the more you will become aware of the types of subtly and not so subtly used gimmicks that are incorporated into their construction. The more aware of those gimmicks you become, the less you will get fooled by them.