medium · SAT Reading & Writing

While many nineteenth-century biologists assumed that deep-sea organisms were relics of an ancient era, recent genomic analysis of certain benthic crustaceans suggests a more complex history. The data indicate that several lineages actually descended from shallow-water ancestors that migrated to the abyss much later than previously thought. Which choice best describes the overall structure of the text?

1. It identifies a common misconception about crustaceans and then argues that all deep-sea life is relatively young.
2. It explains a specific biological mechanism and then traces its evolution across several geological eras.
3. It presents a long-standing scientific assumption and then describes a discovery that challenges it.
4. It notes that deep-sea organisms are considered ancient relics and mentions that crustaceans are a key subject of study.

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