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Problem 12 - Olympiad

Researchers are investigating the spread of an invasive plant species in a wetland. Theory X proposes that the plant's success is primarily due to its rapid asexual reproduction, allowing it to quickly colonize new areas. Theory Y suggests that the invasive plant releases allelopathic chemicals that suppress the growth of native species, giving it a competitive advantage. Which experimental result would provide the strongest evidence in favor of Theory Y?

Correct: B

Theory Y specifically states that the invasive plant 'releases allelopathic chemicals that suppress the growth of native species.' Laboratory experiments demonstrating that extracts from the invasive plant inhibit the germination of native seeds (Choice B) would provide direct evidence of allelopathic effects, thus strongly supporting Theory Y. Choice A describes a general competitive advantage but doesn't specify the mechanism. Choice C supports Theory X's rapid reproduction. Choice D is consistent with the invasive plant having a negative effect, but doesn't pinpoint allelopathy as the mechanism.