Self-study
Meteorologist: Conclusion Heavy downpours are likely to become more frequent if Earth's atmosphere becomes significantly warmer. █ ████ ██████████ █████ ███ ███████ ███████ ██ ██████ ████████████ ███ ███ █████████ █████ █████ █████ ████ ██████ ████ ████████ █ ██████ ██████████ ████ █████ ████ █████████ █████████ ██ ██████ ███████ ██ ████████ ██ █████ █████ ██ ██████ ██████ ██████████ ███████ █████████ ███ ████ ██████ ██ ███████
A Causal Chain Supporting a Prediction
The meteorologist predicts that if Earth's atmosphere becomes significantly warmer, heavy downpours are likely to become more frequent. The rest of the stimulus explains why this prediction makes sense, by laying out a causal chain that connects a warmer atmosphere to heavier, more frequent downpours.
Here's how the chain works. A warm atmosphere heats the oceans, which speeds up evaporation, and the resulting water vapor forms rain clouds more quickly. Separately, a warmer atmosphere holds more moisture, which produces larger clouds. And when water vapor in those larger clouds condenses, heavier downpours are more likely.
Start
warmer atmosphere
leads to
leads to
clouds form
faster
faster
larger clouds
leads to
leads to
heavier
downpours
downpours
leads to
more frequent heavier downpours
End
The right path shows how a warmer atmosphere leads to larger clouds, which lead to heavier downpours. The left path shows how a warmer atmosphere makes clouds form faster. Both feed into the conclusion: more frequent, heavier downpours.
This means the first sentence is the conclusion, and the last three sentences are all premises. Each premise is one link in the causal chain.
What Role Does the Last Sentence Play?
We're asked about the role of the last sentence: "in general, as water vapor in larger clouds condenses, heavier downpours are more likely to result." This is the final link in the right path of the causal chain. It connects "larger clouds" to "heavier downpours."
This sentence is a premise. It's one piece of the support for the prediction in the first sentence. It is not a conclusion of any kind, because no other sentence in the stimulus is offered to prove it. Yes, it connects to the other premises in the chain, but being part of a chain is not the same as being supported by the other links.
Think about it this way: if you asked the meteorologist, "Why should I believe that larger clouds lead to heavier downpours?" she couldn't point to either of the other premises as an answer. The claim that a warm atmosphere heats the oceans and speeds up evaporation doesn't help prove that larger clouds produce heavier rain. Neither does the claim that a warmer atmosphere holds more moisture and creates larger clouds. Those premises sit alongside the last sentence as separate links in the chain.
So we're looking for an answer that says the last sentence is a premise.
17.
Which one of the following ████ ██████████ █████████ ███ ████ ██████ ██ ███ ███████████████ ████████ ██ ███ █████ █████ ██ ████████ ██ █████ █████ ██ ██████ ██████ ██████████ ███████ █████████ ███ ████ ██████ ██ ███████
a
It is the ████ ██████████ ██ ███ █████████
The last sentence isn't a conclusion at all. The only conclusion in the argument is the first sentence, the prediction that heavy downpours are likely to become more frequent if Earth's atmosphere warms significantly. The last sentence is a premise that helps support that prediction. It's one link in the causal chain, not the point the meteorologist is trying to prove.
b
It is the ██████████ ██ ███ ████████ ██ █ █████ ███ ██ ███ ███ ████ ██████████ ██████ ██████████ ██ ███ █████████
This has two problems. First, the last sentence isn't the conclusion of the argument as a whole. That's the first sentence. Second, (B) says there are other explicitly stated conclusions in the argument besides the main one. But there's only one conclusion here. None of the last three sentences function as intermediate conclusions, because none of them receive support from any other sentence.
c
It is a █████████ ████ ███ ████████ ██ ████████ ██ ███████ ███ ██ ███ ███ ██████████ ██ ███ ████████ ██ █ ██████
This says the last sentence is something the argument is intended to support, which would make it some kind of conclusion. But it's not. No other premise in the stimulus is offered to prove that larger clouds lead to heavier downpours.
You might be drawn to (C) because the last sentence has obvious connections to the other premises. After all, it's one link in a causal chain, and the previous link ("warmer atmosphere produces larger clouds") feeds into it. But having a connection to another premise is not the same as being supported by that premise. "A warmer atmosphere creates larger clouds" tells us where larger clouds come from. It doesn't help prove that larger clouds lead to heavier rain. That's a separate factual claim the meteorologist simply asserts. So the last sentence remains a premise, not a conclusion.
d
It is used ██ ███████ ███ ████ ██████████ ██ ███ █████████
This accurately describes the role of the last sentence. The argument has only one conclusion: the prediction in the first sentence. The last sentence is one of three premises that support it. Specifically, it's the link in the causal chain that connects larger clouds to heavier downpours.
e
It provides a ██████ ███████████ ██ ███ ██████████ █████████ ██ ███ ██████████ ██ ███ ████████ ██ █ ██████ ███ ██ ██ ███ ████████ ██ ███████ ███████ ███ ████ ███████████
The first half of (E) is reasonable. The last sentence does provide a causal explanation that relates to what the conclusion describes. But the second half is wrong. The last sentence absolutely is intended to support the conclusion. It's one of the premises in the causal chain the meteorologist builds to justify her prediction. If the last sentence weren't meant as support, it would just be a random observation with no purpose in the argument.