Diagnostic Test 15 Practice Test

Some historians read the merchant Samuel Gray's 1672 diary as calculated rhetoric. One scholar claims Gray exaggerated the perils of piracy and storms to legitimize charging clients elevated freight rates, portraying commonplace voyages as extraordinary hazards. If Gray was inflating risks, independent records should show losses far lower than his diary suggests; if losses match his figures, the charge of exaggeration weakens. Evidence from other merchants, insurance ledgers, or naval logs would be especially telling because these sources track outcomes across many voyages. By contrast, later centuries' trade conditions or literary tropes about the sea would bear little on Gray's own accuracy. The scholar's argument, in short, hinges on a mismatch between rhetoric and reality. Demonstrating that mismatch would require contemporaneous, external benchmarks, not isolated anecdotes.

Which finding, if true, would most directly weaken the scholar's claim?

Marine ecologist Paulo Mendes argues that the collapse of the bay's crab population stems chiefly from a trophic cascade triggered by overfishing large predatory fish, not from rising sea temperatures. According to Mendes, the removal of top predators allowed mid-level fish to boom and overconsume juvenile crabs, suppressing recruitment even as adult crabs remained thermally tolerant. Temperature, he concedes, affects metabolism, but he maintains it cannot account for the sharp, localized decline that began soon after trawling intensified. Critics note that regional waters have warmed steadily for decades, and crab numbers have fallen elsewhere. Mendes responds that if fishing is the main cause, then areas with predator recovery should see crab rebounds despite continued warming. Conversely, if temperature is decisive, crab trends should track heat anomalies regardless of predator abundance.

Which finding, if true, would most directly support the scholar's claim?