Question Type:
Necessary Assumption
Stimulus Breakdown:
Conclusion: The snail must have learned to associate the bright light with the shaking of the tank.
Evidence: Experimenters [obnoxiously] shone a light into the tank while shaking it. The snail tensed its foot in response. Later, they JUST shone the light, and the snail still tensed its foot.
Answer Anticipation:
Assumption: snails are receptive to Pavlov's Classical conditioning. (jk) If we were to adopt the Anti-Conc mindset, we'd have to think of a way to argue that the snail did NOT ever learn to associate the bright light with the tank shaking. So how, then, would we explain why the snail tensed its foot, even when the tank wasn't shaken? Hmm. Maybe snails tense their foot in response to bright light? The author would have to assume that this is not the case.
Correct Answer:
D
Answer Choice Analysis:
(A) Extreme = "all", "same". The conclusion is about THE snail, not "snails", so there's not any reason the author needs to assume that this snail is representative of other snails.
(B) Close, but not quite. If snails ARE ordinarily exposed to bright lights, it might be harder for them to learn to pair bright light with tank shaking, but it's still possible.
(C) This is the same as (A). Since this is about THE snail, not "snails", there is no assumption of representativeness going on.
(D) Yes! This was our prephrase. If we negate this, we get "the bright light alone WOULD usually cause the snail's foot to tense". If that's true, then when we ONLY shine a light into the tank and we see that the snail tenses it's foot, we already have the explanation why: the bright light did it.
(E) This is a real world trap. In Classical Conditioning, you would probably always be dealing with an instinctual response (dogs' salivating in response to food) and then try to pair it with an arbitrary stimulus (ringing a bell). But this argument doesn't actually presume anything about classical conditioning. The author's argument isn't impacted if the tensing is a learned response. I could shine a bright light while someone sneezes, and the subjects would react with their learned response of saying "Bless You". Later, if shining the bright light alone makes the subjects say "Bless You", I can still argue that the subjects must have learned to associate the shining of the light with someone sneezing.
Takeaway/Pattern: This argument can be pretty much "solved" up front, and this starts by assigning yourself the Anti-Conclusion mindset. If an author is concluding some Interpretation of / Explanation for her background facts, our primary job is to think of some Alternative Explanation for the same facts. Here, the author was trying to explain why the snail would tense its foot in response to JUST the bright light. The least creative alternative explanation, "the light causes the foot to tense", was all that was being tested.
#officialexplanation