Question Type:
Inference
Stimulus Breakdown:
The stimulus contains two conditional statements:
cultivated → people discovered agriculture 1000s of years before other known instances
~ cultivated → people ate wider variety of plants than any other groups at the time
Answer Anticipation:
Since the stimulus contains conditional statements, we should watch out for incorrect answers that try to negate or reverse those statements incorrectly.
Correct Answer:
(B)
Answer Choice Analysis:
(A) Out of scope. Nothing in the stimulus is about determining which types of plants these are. We only know what can be concluded if they are of one type or the other.
(B) Correct. If the plants were cultivated, we have support for the idea that people at the site were using some plants—the cultivated ones—in ways that no one else was. But what if the plants were wild? In that case we know that these people ate a wider variety of wild plants than any others at that time. "A wider variety" supports the idea that they were eating types of plants that other people weren't. Is this 100% provable from the facts in the stimulus? No, but it doesn't have to be, since this question asks us to find the answer that is "most supported."
(C) Invalid reversal. This answer choice talks about reaching a "more advanced stage in the use of wild plants." This corresponds most closely to eating "a wider variety of wild plants" in the last sentence in the stimulus. However, choice (C) presents an invalid reversal of that last sentence. If choice (C) read, "if the people had not reached a more advanced stage in the use of wild plants than any other people at the time, then the plants at the site were cultivated, that would be a reasonable contrapositive.
(D) Invalid reversal. This is a reversal of the second sentence in the stimulus.
(E) Unsupported comparison. The stimulus doesn't give us any reason to think one scenario is more likely than the other.
Takeaway/Pattern: Remember that there are two types of Inference questions: ones that ask for an answer that must be true, and ones that ask for the answer that is "most supported." For both types, but especially in the latter case, working from wrong to right is the key. Eliminate the four answers that are most clearly incorrect.
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