Question Type:
Inference (Most strongly support)
Stimulus Breakdown:
We found some material (I/T/C, but no heavy) in the atmosphere downwind from a power plant.
The material came from Fuel Rods or the Core.
The Fuel Rods never have T (infer: the T must have come from the Core. We still don't know where the I and C came from).
If stuff had ejected out of the Core, it would have included heavy.
The material we found had no heavy (infer: by contrapositive, the material did not eject out of the Core).
There was some steam released that might have come into contact with the core. The core has I/T/C, and I/T/C is easily absorbed into steam clouds.
Answer Anticipation:
Jeez, what a nightmare. The two biggest themes of Inference are Conditional Logic and Causality. This had both, and more. We had two conditional rules that we were able to apply to specific facts:
("If it came from Fuel Rods, then no T" + "This material had some T in it" = The T in the material did not come from the Fuel Rods.)
("If radioactive material ejects into atmosphere directly from the Core, then it would have heavy isotopes" + "this radioactive material in the atmosphere did not have heavy isoptopes" = This material did not eject directly from the Core.)
The T didn't come from the Fuel Rods, and it didn't eject directly from the Core. Yet, we know this material came from Fuel Rods or Core. We're only left with the possibility that it came from the Core, but it didn't eject directly from it. How do we solve this mystery? Steam ... which apparently blew by the Core and picked up some I/T/C, which we later detected downwind from the power plant.
Correct Answer:
B
Answer Choice Analysis:
(A) This is trying to make a fake blend of the two conditional rules. We only know that directly ejected stuff wouldn't have heavy isotopes. It could potentially have T.
(B) Yes! It's not 100% provable, but this is "most strongly supported". It's the #1 suspect for solving the mystery of where the I/T/C material came from.
(C) We never talked about functional vs. damaged. We know that T didn't come from the Fuel Rods, but they still might have been damaged.
(D) This is a tempting overreach. Since we know the Fuel Rods didn't contribute the T to the I/T/C material, we might be tempted to think, "I guess the Fuel Rods provided the I and C, and the Core provided the T." But we have no support for making that division. It could just as easily be that Fuel Rods provided C and the Core provided I/T. It could just as easily be that Fuel Rods provided nothing and the Core provided I/T/C.
(E) Just like (A), this is trying to make a fake blend of the two conditional rules. We only know that Fuel Rods don't have T. We have no idea whether they have heavy.
Takeaway/Pattern: This is a very tough question (in my opinion). We might get it right by sensing that the other ones are wrong, but it definitely takes some time to organize all the information, make the correct inferences as you go, and arrive with the "Detective's Hypothesis" at the end that, "The steam did it."
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