Marine biologist Ana Reyes hypothesizes that cleaner shrimp attract reef fish through movement: the shrimp perform a rocking "dance" that signals they will remove parasites rather than flee or attack. To test the idea, her team filmed cleaning stations on a Caribbean reef and recorded how often passing fish stopped at each station.
Which finding, if true, would most directly support Reyes's hypothesis?
Pick an answer to get instant coaching from Sage.
Run "Predict the winning evidence first": if the dance attracts fish, the proof is more fish stopping when the shrimp dances than when it sits still. A is exactly that result. B, C, and D are all true-but-irrelevant, timing, parasite counts, and station location, none of which touch whether the movement draws fish.
Reyes's hypothesis is that the dance attracts fish, so the proof is fish responding to the dance by stopping more. Choice A supplies exactly that comparison: more stops when the shrimp danced than when it was still. Choice B describes when the dance happens, not whether it draws fish. Choice C shows that cleaning occurred but says nothing about the dance causing fish to approach. Choice D concerns where stations sit, which is unrelated to whether movement signals the fish.
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