For years, scientists have proposed the idea that Mars was o

Question

For years, scientists have proposed the idea that Mars was once covered by two huge oceans. However, ridges of rock in the northern hemisphere that seem to resemble a shoreline are too hilly to be the edges of an ocean. If it could be shown that something caused an imbalanced portion of the planet’s mass to shift from these ridges of rock toward the equator, where the mass now lies, it is possible that the ridges were once actually smooth.

Which of the following can be inferred from the statements above?

A. If it is determined that the ridges of rock in the northern hemisphere of Mars were never smoother than they now are, oceans did not exist on the planet.
B. The discovery that some of Mars’ equatorial mass was once part of northern-hemisphere rock ridges would support the idea that the planet was once covered by oceans.
C. If the rock ridges in the northern hemisphere of Mars were smooth at one time, some the planet’s mass was once closer to the equator
D. In order for a planet to have oceans, a portion of the planet’s mass must have been shifted towards the equator.
E. There is general agreement in the scientific community that Mars does not have the right atmospheric conditions to support an ocean.

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mikemcgarry · Accepted Answer

. Dear bkpolymers1617 & nightblade354 , I'm happy to respond.

Like many Veritas questions, this is exceptionally well written, and I agree with the OA of (B). First of all, notice that (A) is over-the-top wrong. If this one ridge were never smooth and therefore never a coastline, then that would take away one possible coastline of one possible ocean. The prompt says that scientists (presumably for other good reasons) " have proposed the idea that Mars was once covered by two huge oceans ." Why would eliminating the evidence for one coastline mean no oceans at all? Choice (A) is far too extreme. (B) is a very solid answer. To bkpolymers1617 , I will say: remember that we are talking about science here. We are talking about a meticulous and highly data-driven field. If scientists say that " ridges of rock in the northern hemisphere . . . seem to resemble a shoreline ," this is NOT a matter of one or two people simple scratching their heads and say, " Gee, that kinda seems like a shoreline ." Instead, such a statement is based on a tremendous amount of numerical data and computer modeling. Planetary geology is not my field. Let's say, for the sake of argument, that a shoreline has 20 known features. If some planetary geological structure has, say, 3-4 of these features, no responsible scientist is going to say that it "seems" like a shoreline. If a geological feature has more than 15 of these 20 features, that when scientists would even start to consider advancing a claim. You have to understand that scientists are, by nature and by profession, some of the most conservative people on earth in terms of the claims they are prepared to make. Unlike lawyers, unlike business people, unlike politicians, scientists almost never will open their mouths about a topic unless they already have a mountain of data starting to point in a particular directions. Even a "seems" statement from a scientist carries far more weight they just about anything a politician says with 100% conviction! The most likely reason the word "seems" appears at all is that this " ridge of rocks ," despite the tremendous evidence suggesting that it was a shoreline, is " too hilly ." In a way, this is a paradox: we have tremendous evidence that this was a shoreline, but it has this one feature that is not consistent with where all that evidence was pointing. My friend, it is not enough to pay attention to the words of the argument. The GMAT CR is about characters. Like arguments in the real world, the arguments on the CR come from particular people with particular perspectives and agendas, and you need to be aware of that that. When a politician claims " X is a sure thing !," that doesn't mean 1% of what it means when a scientist tentatively says, " Evidence is beginning to suggest X ." Everyone has a background and an agenda, if you don't understand that, you will not understand that person's argument. Does all this make sense? Mike

akhil911 · Answer

Solution
Answer: B

Explanation: The final sentence states that if some of the planet’s mass shifted toward the equator, the ridges might have once been smooth. We are told in the second sentence that the ridges now are too hilly to be the edges of an ocean. Discovering that some of the mass was once further from the equator implies that it shifted closer to the equator, supporting the idea that the planet could have been covered with oceans.

(A) This cannot be inferred because it remains possible that oceans once existed in the southern hemisphere.

(C) This cannot be inferred because it is possible that the ridges were once smooth without the mass being closer to the equator. We are not told otherwise.

(D) We do not have enough evidence to say that the shifting of mass is necessary for the existence of oceans.

(E) The atmospheric conditions are not mentioned in the stimulus.

paranoidvik · Answer

Its between option A and B. 
C. Out of scope
D. reverse relationship 
E. Out of scope

option A is the might be true category, Absence of smoothness of rock of northern hemisphere cannot indicate that oceans were absent. Because we do not have southern hemisphere data we cannot say this accurately

Option B: This would increase the likelihood of the presence of oceans on the planet

ddg · Answer

I think another likely point to miss out and mislead people into selecting A is:
Nothing in the passage gives us information about what can or could be concluded if the rigid rocks of NH are not proved to be smooth in the past. What other information compels us to think oceans didn't exist? OFS = out of scope.

Hence left with B.

Vishvesh88 · Answer

A. If it is determined that the ridges of rock in the  northern hemisphere  of Mars were never smoother than they now are,  oceans did not exist on the planet. 
B. The discovery that some of Mars’ equatorial mass was once part of northern-hemisphere rock ridges would support the idea that the planet was once covered by oceans.
C. If the rock ridges in the northern hemisphere of Mars were smooth at  one time , some the planet’s mass was once closer to the equator
D. In order for  a planet  to have oceans, a portion of the planet’s mass must have been shifted towards the equator.
E. There is general agreement in the scientific community that Mars does not have the right atmospheric conditions to support an ocean.

A. The argument speaks about only the northern hemisphere. Oceans may have been present in the southern hemisphere. OUT.
B. Yes. The Argument states that the if the rocks were smooth, means a part of the planet's mass should have moved towards the equator and hence, planet may have been covered by oceans. 
C. This is a tricky one. This answer could be a viable option if the the words "one time" were not used. "One time" widens the scope of the argument and introduces possibilities. OUT.
D. The planet spoken of is Mars. Other planets do not come under the purview. OUT.
E. Irrelevant. OUT.

aragonn · Answer

This is a inference question and right approach is to try to prove a choice is wrong else it is the answer. I have tried the same over here. Please someone help me to sort it out.

A. If it is determined that the ridges of rock in the northern hemisphere of Mars were never smoother than they now are, oceans did not exist on the planet. ---  scientists have proposed the idea that Mars was once covered by two huge oceans, so lets not think about it. very unlikely for this choice to be true. 
B. The discovery that some of Mars’ equatorial mass was once part of northern-hemisphere rock ridges would support the idea that the planet was once covered by oceans.  ---- what if this is true is it sufficient to determine the hypothesis. what if this is yes but edges were not smooth??? not sure for this choice. 
C. If the rock ridges in the northern hemisphere of Mars were smooth at one time, some the planet’s mass was once closer to the equator  ---- baseless choice. 
D. In order for a planet to have oceans, a portion of the planet’s mass must have been shifted towards the equator.  ---- smooth edges or not, but this choice is definetly true. 
E. There is general agreement in the scientific community that Mars does not have the right atmospheric conditions to support an ocean.  --- baseless.

bkpolymers1617 · Answer

GMATNinja : Can you please clarify a doubt here. I believe that this question is wrong. The official source says that B is the answer. But my question is that Option B mistakes a could be true answer to something that is definitely true. What I mean is that the argument first of all says the ridges of rock seem to be a shoreline(so this is a kind of a week assumption, not something hard and solid) and then it showcases that a shift of mass would ideally point towards the fact that these shore lines were once smooth - But, again don't you think that if the very assumption of these rock ridges being shorelines once is wrong, then the ocean theory would not hold true despite the fact that there was a shift in mass. So I believe that option B, if worded correctly with something like this would be the right answer.

b) The discovery that some of Mars’ equatorial mass was once part of northern-hemisphere rock ridges would support the idea that the planet could have been ~~(was)~~ once covered by oceans.

Can you please validate this?

b) The discovery that some of Mars’ equatorial mass was once part of northern-hemisphere rock ridges would support the idea that the planet could have been  (was)  once covered by oceans.

Can you please validate this?

nightblade354 · Answer

I couldn't agree more, which is why I chose A over B. If an expert could weigh in on this it would be a big help.

bkpolymers1617 · Answer

mikemcgarry  : CAN YOU HELP PLEASE? Please see last 2 posts.

atomicmass · Answer

bkpolymers1617   nightblade354

For those who think option A could be the answer

On an inference question when you see wordings like option A it is almost always wrong. Let me explain how:

Running keeps a person fit.

Consider below 2 options:
A -> If a person is not running he is not fit.
B -> running treadmill might help a person to be fit.

Now, A is 100% wrong as there are other ways, which can help a person, to remain fit.

RanjanSury · Answer

Good one.

B is the best choice here.

(A) Reverse Logic: Just because ridges were never smooth, doesn't necessarily mean that oceans never existing. There could be a variety of other factors not considered 
 (B) Yes. This is exactly the point that the author is trying to make. 
 (C) This isn't a valid inference. We are more concerned about the whether ocean existed.
(D) This choice is too narrow. 
(E) Atmospheric conditions ? Not supported by the passage.

Bunuel · Answer

VERITAS PREP OFFICIAL SOLUTION:

Answer: B

Explanation: The final sentence states that if some of the planet’s mass shifted toward the equator, the ridges might have once been smooth. We are told in the second sentence that the ridges now are too hilly to be the edges of an ocean. Discovering that some of the mass was once further from the equator implies that it shifted closer to the equator, supporting the idea that the planet could have been covered with oceans.

(A) This cannot be inferred because it remains possible that oceans once existed in the southern hemisphere.

(C) This cannot be inferred because it is possible that the ridges were once smooth without the mass being closer to the equator. We are not told otherwise.

(D) We do not have enough evidence to say that the shifting of mass is necessary for the existence of oceans.

(E) The atmospheric conditions are not mentioned in the stimulus.

VerbalBot · Answer

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