Although fullerenes - spherical molecules made entirely of carbon-were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite. Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypothesis about the state of the Earth's crust at the time these naturally occuring fullerenes were formed. Which of the following, if true, most seriously undermines the argument? (A) Confirming that the shungite genuinely contained fullerenes took careful experimentation. (B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft. (C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed. (D) The naturally occuring fullerenes are arranged in a previously unknown crystalline structure. (E) Shungite itself is formed only under distinctive conditions

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Although fullerenes - spherical molecules made entirely of carbon-were

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AndrewN

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01 Jul 2022, 12:22

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PyjamaScientist

Hi AndrewN,

I hope you are doing great.

Though I got this question right (mainly on the basis of POE), one word "previously" in the correct answer choice threw me off.
What does "previously" do here?

(D) would be just as correct without the "previously", so I am not quite able to comprehend its "relevance" here.
I believe one more person here had asked the same question, but it was unanswered. So, if you could enlighten me as well as the larger crowd, it would be highly appreciated.

Hello, PyjamaScientist. I would argue that previously is, in fact, vital to answer choice (D). It tells us that the fullerenes found in nature are known to be arranged in a different crystalline structure from the lab-generated fullerenes. Consider the answer choice without previously:

(D.2) The naturally occurring fullerenes are arranged in an unknown crystalline structure.

By itself, unknown cannot be interpreted to mean necessarily different. For instance, many sea creatures at the bottom of the ocean could be speculated to possess unknown physical features, but previously unknown physical features would indicate that they have actually been observed or studied. Sure, another adjective besides unknown could function on its own in a similar capacity—different comes to mind, as does unique—but in the context of the answer choice, previously unknown must be considered together for (D) to be correct.

Thank you for thinking to ask.

- Andrew

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31 May 2023, 04:38

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B seems like a relevant weakener to me. If the fullerenes from earth didn’t originate in the earth’s crust but instead are there because of meteorite crashes it would seriously weaken the argument.

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Pre-thinking - What if the fullerenes in nature are formed by some other process, or they are not similar in structure to the ones formed in the Lab? In that case we'll not get to know about the state of Earth's crust. The scope of the argument is limited to finding new information that is aligned with the scope of the argument - laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure; this discovery should give geologists a test case for evaluating the hypothesis about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation. - Out of scope
(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft. - maybe the same conditions on the meteorite. Distortion
(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed. - Out of scope.
(D) The naturally occuring fullerenes are arranged in a previously unknown crystalline structure. - per our thinking
(E) Shungite itself is formed only under distinctive conditions- We know that. Distortion

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10 Oct 2025, 00:39

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Passage Analysis

Although fullerenes—spherical molecules made entirely of carbon—were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.

Almost everyone gets the sentence right. The statement presents a contrast indicated by the word although. It talks about molecules, fullerenes. These are spherical molecules made only of carbon. The molecules were first found in the lab, but they have been found in nature after that. And in nature, they were formed in fissures of the rare mineral shungite.

Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure

The sentence starts with the word since. There are going to be two parts to this sentence. The first part is going to present a support or a reason for the second part. This first part says that the lab synthesis of the fullerenes, the molecules that we have talked about, requires specific conditions of temperature and pressure. If you want to create the molecules in a lab, you need a unique set of conditions of temperature and pressure.

this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.

This is a part that people rarely ever understand. The most common interpretation of this statement that I have seen is that the discovery should tell us something about the state of the Earth's crust. If you also understand this much, then you are faltering on the comprehension. A very common reason people falter in comprehending this statement in one go is that the statement is pretty complex, so they can't do justice to it in one go. So they end up with a superficial meaning of this statement.

Let's try to understand this. It says that this discovery... what does this discovery refer to?

Here some people think that this discovery refers to the part in the since clause. But when I ask them, "Is that a discovery?" there is nothing to suggest that the since part is a discovery. So then they backtrack. The discovery here refers to the finding of the fullerenes in nature.

The sentence says that that discovery should give geologists a test case to evaluate some hypothesis. So we already have some hypothesis that you're trying to evaluate using this discovery.

What does evaluation mean?

Evaluation means figuring out whether our hypothesis is correct or not. So this discovery should help us do that.

What is the hypothesis about?

The hypothesis is about the state of the Earth's crust.

What does the state of the Earth's crust mean?

Again, there could be multiple parameters defining the state of the Earth's crust, but we have so far talked about temperature and pressure. So I will think that, okay, it's talking about the temperature and pressure of the Earth's crust.

At what time? At the time these naturally occurring fullerenes were formed. So let's say these naturally occurring fullerenes were formed 2000 years ago. So we are talking about the hypothesis about what the temperature and pressure of the Earth's crust was 2000 years ago, and the finding of fullerenes in nature will help us evaluate this hypothesis.

How will that finding help us evaluate this hypothesis?

This is something that people don't take a pause to think about. Whenever a statement that is a part of a paragraph or a passage makes a link, we have to take a pause to understand how that link makes sense, given the context set up.

In this specific case, if you look at the since part, the since part says in the lab, you require a set of specific temperature and pressure, right? And this hypothesis is about the temperature and pressure of the Earth's crust 2000 years ago. Now, if these fullerenes are found in nature, then the natural conditions at the time these fullerenes were formed must be the lab conditions that are required to create fullerenes. So we have a test case.

Basically, this discovery tells us that the state of the Earth's crust 2000 years ago was what the lab conditions are required. If the hypothesis is saying the same thing, the hypothesis is strengthened by this discovery. On the contrary, if the hypothesis is saying something different about temperature and pressure, the hypothesis is weakened by this discovery.

For example, if the lab conditions required for fullerenes are 50°C temperature and 100 units of pressure, now, given the discovery, we have a reason to believe that the state of the Earth's crust 2000 years ago was 50°C temperature and 100 units of pressure. If a hypothesis about the Earth's crust 2000 years ago is also saying that it was 50°C temperature and 100 units of pressure, then the hypothesis is strengthened. If, on the other hand, the hypothesis is saying the temperature was 20°C and the pressure was 60 units, then the hypothesis is weakened by the discovery.

So that is how this discovery will give us a case to evaluate this hypothesis. That is the comprehension of the statement.

The overall gist of the argument is that these fullerene molecules were initially formed in the lab, but they have since been found in nature. And their finding in nature will help us evaluate the hypothesis about the state of the Earth's crust when these fullerenes were formed.

Why? Because these fullerenes require a specific set of temperature and pressure, and that must be the same in the Earth's crust whenever these fullerenes were formed. So if the hypothesis is saying the same thing, then the hypothesis is strengthened; otherwise, the hypothesis is weakened.

Options Evaluation

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.

Incorrect. This option says that to confirm that the mineral shungite actually contained fullerenes required careful experimentation, so it took some effort to confirm.

This is not relevant to the argument. Whether confirming this took careful experimentation or whether it was a straightforward task does not impact the argument because we are given that fullerenes have been found. We have to take that as a fact. Whether that finding was easily done or took some effort has no impact on the argument.

(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.

Incorrect. This is a very popular option. I think the reason many people mark this option is that they think that if some fullerenes have been found on the remains of a small meteorite, then the discovery of the fullerenes cannot really tell us about the state of the Earth's crust. The discovery should tell us about the state of the meteorite.

This logic would have worked fine if the option had stated: "Some fullerenes have also been found on the remains of a small meteorite that was found next to the mineral shungite." In that case, we would have reason to believe the fullerenes that we have found in shungite have probably come from the meteorite. However, in the present case, this logic does not work because the option says that the meteorite collided with a spacecraft. The meteorite has not even been found on Earth, let alone anywhere close to shungite.

Think about it. If a meteorite that fell on some other part of the world also contains fullerenes, do you start doubting your discovery of fullerenes and think that these fullerenes would have also come from that particular meteorite that fell in some other part of the world? No, that does not make sense. In this case, the meteorite collided with a spacecraft. It's nowhere close to where we have discovered the fullerenes, so it does not make sense to think that our fullerenes have come from the meteorite.

I think this is an excellent play on a gap that a lot of people can think about, but the option just goes completely off while starting off in the right direction, and people just don't notice that. This option has no impact.

(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.

Incorrect. This option also has no impact. Whether the mineral shungite contains large amounts of carbon or does not contain any carbon has no impact on the argument.

Again, some people may think that, well, if they formed from the carbon contained in the mineral shungite, then the fullerenes have not really formed in the Earth's crust. But this logic does not make sense because the mineral shungite would also be in the Earth's crust, right? It's not out there in space. So, whether fullerenes formed from the carbon from the mineral shungite or from some other carbons has no relevance to the argument.

(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.

Correct. This option weakens the argument. It's a cleverly worded statement. Its meaning is that the naturally occurring fullerenes are arranged in a crystalline structure that was not previously known.

How is this "not previously known" relevant? This is very relevant because if you look at the chronology of the discovery, the fullerenes were first discovered in the lab. Then they were discovered in nature. By saying that the naturally occurring fullerenes are in a previously unknown structure, the statement indicates that the structure of these fullerenes is not the same as the structure of the fullerenes that were found in the lab.

Now, if the structure is not the same, can we say that they still require the same temperature and pressure as the lab-synthesized ones? No, we cannot say that. Now we have a doubt. These naturally occurring fullerenes could require a different set of temperature and pressure, and we don't know that set; we only know the temperature and pressure conditions required in the lab.

In that case, the discovery would not help us evaluate the hypothesis because we don't even know the temperature and pressure required for the naturally occurring fullerenes. This is a weakener.

(E) Shungite itself is formed only under distinctive conditions.

Incorrect. This option has no impact. Whether shungite is formed under distinctive conditions or not has no relevance to the argument. The argument is about using the distinctive conditions of fullerenes to evaluate the hypothesis. Whether shungite is formed under distinctive conditions or can be formed in a variety of conditions has no impact on the argument.

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02 Nov 2025, 10:51

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*This discovery should give geologists a test case*

When they say this, are they referring to the discovery of natural fullerene or the lab one? If it's the natural fullerene, then maybe they are using the natural fullerene as a test case and not the lab grown one. But the reasoning for D assumes the geologists would be using the lab grown one for testing.

Based on how the passage is written, it seems very evident that "this discovery" refers to the discovery of the natural fullerene.

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12 Nov 2025, 15:20

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kraizada84

Basically the thing is :
F found in lab first then in nature, as they can be synthesized in lab argument concludes that okay it is possible to know something about the earth's state when these naturally occurring F were found. But what about if geologists dont know there structure prior to the point when discovery was made then its useless having F in lab. Because its no concrete source to make the conclusion.

Previously Unknown means before the discovery nothing about the structure is known. Hence if nothing is known till that point we cant say anything regarding the conclusion and hence conclusion stands is weakened.

Hope this helps..!!

True! but the conclusion was made post the discovery of natural and lab grown F. Post the discovery of natural F, it's structure is known now. So, the author may have very well been through both these statements while deriving her conclusion. How can we be sure that the now known structure of natural F is different from lab F? people don't know something until they discover it right, according to option D?

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12 Nov 2025, 21:21

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The Argument Says: "Lab fullerenes need specific conditions. We found natural fullerenes. So we can use lab conditions as a TEST CASE to figure out Earth's crust conditions."

For this to work, what MUST be true?
The lab fullerenes and natural fullerenes must be THE SAME TYPE of fullerene. They must be the same structure.

Option (D): "The naturally occurring fullerenes are arranged in a previously unknown crystalline structure."
Let's break down "previously unknown":

Previously unknown = We've never seen this structure before = This is a NEW, DIFFERENT structure from our lab fullerenes

Let's take an example:

Lab Fullerenes: Soccer ball shape (made at 2000°F, high pressure)

Natural Fullerenes (Option D): Pyramid shape - previously unknown = we've NEVER made this shape in the lab

Question: Can the soccer ball recipe (2000°F, high pressure) tell us how nature made pyramids?
Answer: NO! They're completely different structures. Different structures = formed under different conditions = lab conditions tell us NOTHING about Earth's crust conditions.

Think about it this way:

If natural fullerenes had the SAME structure as lab fullerenes, the GMAT would say: "identical to" or "similar to" lab fullerenes
But it says: "previously unknown" = we've never encountered this arrangement in our labs = it's a DIFFERENT structure

The test case fails because you're comparing two different things.

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28 Dec 2025, 08:16

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GMATNinja can you please help with this question? I did pick (D) purely using the process of elimination, but I somehow don't feel confident that I understood the passage well enough.

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