Recently discovered prehistoric rock paintings on small islands off the northern coast of Norway have archaeologists puzzled. The predominant theory about northern cave paintings was that they were largely a description of the current diets of the painters. This theory cannot be right, because the painters must have needed to eat the from the islands, and there are no paintings that unambiguously depict such creatures.
What this question is testing
Setup
The popular theory says cave paintings show what the painters ate. The author tries to disprove that for these newly found island paintings: he says the painters had to eat sea animals to make it to the islands and back — but they didn't paint sea animals. So the diet theory must be wrong here.
Evaluate
To weaken this argument against the theory, an answer needs to either:
(a) explain why the painters didn't actually need to eat sea creatures (so it's no surprise they didn't paint them), or
(b) explain why sea creatures might have been painted but those paintings aren't around now.
The right answer to "EXCEPT" is the one that does neither — leaves the gap between "needed to eat sea creatures" and "no paintings of sea creatures" intact.
Goal
Find the answer that doesn't address either side of that gap.
Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.