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Problem 1 - Olympiad

Two scientists propose explanations for a recent decline in a local fish population. Scientist 1 suggests that increased agricultural runoff, leading to eutrophication and oxygen depletion, is the primary cause. Scientist 2 argues that overfishing by commercial trawlers, coupled with a natural migratory shift due to ocean current changes, is responsible. Both scientists agree that the fish population is indeed declining. Which of the following investigations would best help to differentiate between the two scientists' hypotheses?

Correct: B

Scientist 1 focuses on water quality (eutrophication and oxygen depletion), while Scientist 2 focuses on fishing pressure and natural migration. Measuring dissolved oxygen levels and nutrient concentrations (Choice B) directly addresses the core mechanism proposed by Scientist 1. If oxygen levels are low and nutrients are high, it supports Scientist 1. If they are normal, it weakens Scientist 1's hypothesis. This direct measurement allows for a clear distinction from Scientist 2's claims. Choice A relates to Scientist 2's natural migratory shift. Choice C relates to Scientist 2's overfishing claim. While both are relevant to Scientist 2, Choice B provides a specific test for the unique aspect of Scientist 1's argument that can help distinguish between the two primary causes.