#16 - The Gulches is an area of volcanic rock that is gashed

[Administrator]

Complete Question Explanation

Must Be True. The correct answer choice is (D)

Scientists accept the flood theory despite the fact that they know of no process that can melt so much ice so quickly. Clearly, the physical effects of water on rock are determined, at least in part, by the speed with which those effects are produced. Otherwise, how can the channels show physical evidence of having been formed quickly? Answer choice (D) is directly supported by the facts in the stimulus and is therefore correct.

Answer choice (A): Just because the channels were cut by running water in the Gulches does not mean that running water is the only thing that can cause deep channels in volcanic rock. This answer choice is an exaggeration and is incorrect.

Answer choice (B): The argument implies no temporal relationship between the formation of the river and that of the channels. Either could have been formed first. This answer choice is incorrect.

Answer choice (C): Just because scientists cannot imagine a process that can melt so much ice so quickly does not mean that they cannot determine the amount of heat required to melt a glacier quickly. In fact, they must know how much heat is required in order to deduce that no currently known process can produce it. This answer choice is incorrect.

Answer choice (D): This is the correct answer choice. See discussion above.

Answer choice (E): Geologists are not rejecting physical evidence: in fact, they are accepting it, even though the conclusion might be unexplainable. This answer choice is incorrect.

[andriana.caban]

Answer choice (E): Geologists are not rejecting physical evidence: in fact, they are accepting it, even though the conclusion might be unexplainable. This answer choice is incorrect.

Hi!

Is it wrong of me to eliminate (E) because the answer choice says "geologists" when the stimulus says "scientists reject the theory." Or, is it general knowledge that geologists = scientists. Also, for (E), you wrote that the Geologists are not rejecting physical evidence. But, the author does state that they originally rejected the theory.

Is (E) wrong in this respect because, instead of answer choice saying that scientists rejected the theory originally.

Would (E) be correct if it had said, geologists are compelled to reject theories that are backed by physical evidence when it is supported by unexplainable premises/evidence?

[KelseyWoods]

Hi Andriana!

We can't eliminate answer choice (E) just because it says "geologists." Geologists are a type of scientist so if something is true of all scientists, then it would also be true of Geologists.

Also, careful with how you're interpreting the wording. The scientists originally rejected the flood theory, it never says they rejected the physical evidence. They rejected the idea that an enormous flood cut the channels; they did NOT reject the physical evidence that showed the channels may have been cut quickly. They could have agreed that the physical evidence seems to show that the channels may have been cut quickly but disagreed on the theory as to what caused the quick cuts.

Hope this helps!

Best,
Kelsey

[SammyWu11201]

Is D correct because it kind of resolves a paradox in the stimulus. How is it that they do not know any natural process that could melt so much ice so quickly, yet the flooding theory is accepted? AC D offers an explanation, and it's the only AC that offers an explanation.

[Rachael Wilkenfeld]

Hi Sammy,

The answer choice isn't a resolve answer because it isn't serving the function of resolving the paradox. Remember for a resolve the paradox answer, we need something that will add information to the stimulus. For a MBT question, we can't add any information---we just go based on what's in the stimulus. Additionally, the answer choice does not actually resolve why it is that the scientists accept the theory now without understanding the process when they didn't accept it in the past.

On the other hand, it is an answer choice that is fully supported by the information in the stimulus. The stimulus tells us that the channels show physical evidence of being formed quickly. We can determine then, that the physical effects of water on rock can vary based on the speed that the water goes. If we can tell from the physical evidence that it formed quickly, we need the physical evidence to show speed. That's all our correct answer choice says here.

Hope that helps!
Rachael