You seem to have gotten to the right answer here without too much trouble, but for those who struggled, I'd like to remind you that this is a sub-category of CR questions called "Draw a Conclusion". The rules surrounding these types of questions are very straightforward: DO NOT MAKE ANY LEAPS OF LOGIC and DO NOT BRING IN YOUR OWN INFORMATION. Everything has to come from what's written (though it will always come paraphrased, so you can't play the "matching game").
Conclusion: No conclusion in Draw a Conclusion questions
Premises: Inconclusive test fails to show truth or untruth. Some employers refuse to hire someone with an inconclusive test.
1. Most examinees with inconclusive polygraph test results are infact untruthful.
Problem: We aren't told anything about how often people do or do not lie, so we can't assume this.
2. Polygraph tests should not be used by employers in the consideration of job applicants.
Problem: Even though this seems like an entirely logical thing to conclude, given the evidence, it is too much of a leap. The passage DOES NOT tell us what should or should not happen in terms of the test.
3. An inconclusive polygraph test result is sometimes unfairly held against the examinee.
Answer: There's no logical "fair" reason to refuse to employ someone with an inconclusive test, so we can assume this directly from what we've been told.
4. A polygraph test indicating that an examinee is untruthful can sometimes be mistaken.
Answer: This is a great example of a "previous knowledge" trap. All of us know (from watching Law & Order) that polygraph tests are not always correct. But is that mentioned anywhere in the passage? No.
5. Some employers have refused to consider the results of polygraph tests when evaluating job applicants.
Answer: Much like D, this would be a logical thing to conclude in real life (some employers must choose to ignore these results if they know they don't tell you much).
Hope that helps!
Tommy Wallach | Manhattan GMAT Instructor | San Francisco
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