Question 115·200 Super-Hard SAT Reading Questions·Information and Ideas
Archaeologists analyzing residue in 3,400-year-old ceramic jars excavated from a desert settlement located more than 200 kilometers from the nearest coast, detected phlorotannins, compounds characteristic of brown seaweeds that begin to degrade within about 48 hours of harvesting. Historical documents from much later periods describe coastal traders sending dried seaweed cakes to inland markets, a process that neutralizes phlorotannins. Because the compounds remained intact in the jars, the researchers argue that the vessels must have once held fresh seaweed.
Based on the researchers’ reasoning, which inference about Bronze Age trade is most strongly supported?
For inference questions, restate the author’s (or researchers’) chain of reasoning in your own words, then ask what must be true if that chain is correct. Eliminate choices that add unstated assumptions (frequency of trade, who used the good, specific preservation methods, or market structure) and choose the option that most directly reflects the necessary implication of the evidence (here, the need to move a perishable good quickly over a long distance).
Hints
Locate the key evidence
Find the detail that connects the jar residue to fresh (not dried) seaweed: intact phlorotannins that degrade quickly and are neutralized by drying.
Use time + distance
Combine “begins to degrade within about 48 hours” with “more than 200 kilometers from the nearest coast.” What does that suggest about how goods had to move?
Avoid adding new claims
Pick the choice that follows directly from the researchers’ freshness argument about trade speed/efficiency, not a choice that introduces frequency of trade, market structure, or preservation techniques not mentioned.
Step-by-step Explanation
Extract the key scientific facts
From the passage:
- The jars were found at a desert settlement more than 200 km from the nearest coast.
- Phlorotannins are characteristic of brown seaweeds.
- Phlorotannins begin to degrade within about 48 hours of harvesting.
- Later documents describe sending dried seaweed cakes inland, and drying neutralizes phlorotannins.
- Because intact phlorotannins were detected, researchers argue the jars held fresh seaweed.
Translate the evidence into a constraint
If the seaweed was fresh (not dried) and its phlorotannins were still intact, then there was a limited time window (on the order of ~48 hours) for the seaweed to be harvested on the coast and end up far inland.
Link the constraint to a trade inference
A short time window combined with a long distance implies that whatever system moved goods from the coast to the desert settlement had to be efficient enough to deliver a highly perishable product before key compounds significantly degraded.
Evaluate each choice against what the researchers’ reasoning supports
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A) This proposes unspecified preservation methods other than drying. The researchers’ reasoning does not rely on (or provide evidence for) alternative preservation; it relies on the implication of freshness.
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B) This claims slow, indirect exchange with long storage stops. That would tend to increase delays and is not supported by the researchers’ argument from intact, quickly degrading compounds.
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C) This adds a claim about how rare or elite the trade was. The passage gives no information about frequency or social use.
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D) This matches what the researchers’ reasoning most strongly implies: to get fresh seaweed (a highly perishable good) more than 200 km inland with compounds still intact, traders needed transportation networks capable of moving such goods quickly.
Therefore, the correct answer is Bronze Age traders maintained transportation networks fast enough to deliver highly perishable goods far inland.