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#6 - Some have argued that body size influences mating

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Complete Question Explanation

This stimulus sets out a somewhat vague causal claim that body size influences mating, and says that it does so "across all societies". It's vague because there is no indication of what the cause is and what the effects are, or whether they are consistent across all societies. In what way does body size effect those decisions? Does it effect them in society A the same way as in society B?

The support for this very broad claim about all societies is based on self-reporting among a select group (university age students) and an analysis of personal ads. That's hardly a representative sample of "all societies", and that's the big, glaring flaw here. The stem asks us to find the answer that best describes that flaw.

Answer A: This is a causal flaw answer that raises the possibility of an alternate cause for both of the stated factors (body size and mating decisions). While there is some vague causality in the stimulus, the cause and effect are so ill defined that a classic causal attack like this one cannot be what we are looking for, especially not when faced with such a glaring problem with the sample.

Answer B: This is the correct answer. This answer choice correctly describes an unrepresentative sample. It makes no difference that the sample in question came from multiple sources, because collectively they still make for a sample group (students and ads) that is not representative of the total (all societies). The group made up of self-reporting students and the content of personal ads is "the sample", and that group is unlikely to represent all societies.

Answer C: Another causal answer here that suggests that the stimulus itself provided evidence of possible multiple alternate or additional causes. This interesting answer actually combines a classic causal flaw (alternate cause) with the less common "internal contradiction" flaw. While fascinating, there was no internal contradiction, and this answer focuses again on the ill-defined causal relationship instead of the glaring problem of an unrepresentative sample.

Answer D: This answer describes an error of division, aka a whole to part flaw, where an author improperly assumes that something that is true of a group must be true of the constituent members of that group. As the stimulus made no claims about any individuals, but only about societies (and not about any individual societies, but about all societies), this does not describe a problem with this stimulus.

Answer E: This describes an evidence error that could be called an over-generalization or a "some evidence in support of a claim is used to prove that claim is true". While it is true that an over-generalization has occurred, there are two solid reasons to reject this answer choice. First, the stimulus did not provide any information about "individual cases". Flaw questions, like Must Be True questions, are based solely on the contents of the stimulus with no outside information allowed. Since this answer describes something that was not in the stimulus, it must be rejected for bringing in new, outside information. Second, an over-generalization answer is typically a weak answer that should be selected only when there is nothing better available. Most of the time there is a better, more specific way to describe the flaw than just to say the author over-generalized, and answer B here is a substantially better answer for being much more specific in the way it described the flaw. Since we are tasked with always selecting the best answer, B must win out over E. Be suspicious of the over-generalization answer, because there may be (and usually is) a stronger, more detailed answer available.
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This may be too detail but I was just wondering...
So in the premise it gives: self-report and ad on newspaper.
Those consists of plural resources right?
Why does B say "a sample"?
I thought E can be right in that sense since it says "cases"
but appearantly this is not individual cases, so E is wrong but...would this small detail not matter?