Question 138·Hard·Text Structure and Purpose
Historical accounts from nineteenth-century ship logs often portray whaling voyages as unpredictable, luck-driven pursuits, which led some historians to argue that the profits of an expedition were largely random. A recent study digitized more than 1,200 voyage journals and cross-referenced harvest dates and coordinates with reconstructed whale migration corridors and sea-surface temperature proxies; it found that the greatest yields clustered where those corridors and temperatures overlapped, and that such clustering intensified as captains accrued experience across seasons.
Which choice best describes the function of the underlined statement in the text as a whole?
For function questions, first bracket the sentence in question and restate it in simple language. Then read the surrounding sentences to see how the passage uses that information: Does it give background, state a claim, provide evidence, or introduce a contrast? Next, summarize the overall logic of the passage (what belief or situation it starts with, what new information it adds, and how that new information affects the original belief). Finally, test each answer choice against that structure, eliminating any that misidentify the sentence’s role (for example, calling background information a “main conclusion” or saying the passage endorses something it actually challenges).
Hints
Focus on what the underlined part actually says
Ignore the answer choices at first. Paraphrase the underlined sentence: what do the historical accounts in the ship logs say about whaling voyages?
Look at the sentence right after the underlined part
Ask: How does that portrayal in the logs affect what historians think? What claim do the historians make because of it?
Compare the historians’ view with the study’s findings
Do the study’s results support the idea that profits were random, or do they show a pattern? How does that relationship help you understand the role of the first sentence?
Match the function, not the wording
Check each answer choice: Does it correctly describe (1) what the underlined sentence is and (2) how it connects to the historians’ claim and the study’s evidence? Eliminate any choice that misstates either the content or the overall relationship.
Step-by-step Explanation
Restate the underlined sentence in your own words
The underlined part says that nineteenth-century ship logs often describe whaling voyages as unpredictable and mainly driven by luck. So, it’s giving a common picture or portrayal of what these voyages were like, according to those historical accounts.
See what immediately follows it
Right after the underlined part, the passage continues: “which led some historians to argue that the profits of an expedition were largely random.” This tells you the effect of that portrayal: because the voyages seemed luck-based in the logs, historians concluded that profits were mostly random.
Understand what the study contributes
The rest of the passage describes a recent study that digitized many voyage journals and compared dates and locations with whale migration patterns and sea temperatures. The study finds that big catches occur where migration corridors and temperatures overlap, and this pattern grows stronger as captains gain experience. That means the study’s evidence suggests profits are not just random luck, but linked to known patterns and learning over time.
Determine the role of the underlined sentence in the whole passage
Putting it all together, the underlined sentence introduces a commonly held portrayal (voyages as luck-driven) that helps explain why historians believed profits were random. The study’s data then shows a non-random pattern, effectively challenging that earlier belief. The best description is: It presents a widely held portrayal of whaling voyages in order to explain why some historians advanced a claim that is later challenged by the study's evidence.