Offshore oil-drilling operations entail an unavoidable risk of an oil

Question

Offshore oil-drilling operations entail an unavoidable risk of an oil spill, but importing oil on tankers presently entails an even greater such risk per barrel of oil. Therefore, if we are to reduce the risk of an oil spill without curtailing our use of oil, we must invest more in offshore operations and import less oil on tankers.

Which of the following, if true, most seriously weakens the argument above.

(A) Tankers can easily be redesigned so that their use entails less risk of an oil spill.
(B) Oil spills caused by tankers have generally been more serious than those caused by offshore operations.
(C) The impact of offshore operations on the environments can be controlled by careful management.
(D) Offshore operations usually damage the ocean floor, but tankers rarely cause such damage.
(E) Importing oil on tankers is currently less expensive than drilling for it offshores.

gmatnub · Accepted Answer

A

B and C strenthen, not weaken
D not related to spill
E not addressing the spill issue

KarishmaB · Answer

Responding to a pm:

Premises:
Offshore ODOs entail an unavoidable risk of an oil spill.
Importing oil on tankers  presently  entails an even greater such risk per barrel of oil.

Conclusion:
If we are to reduce the risk of an oil spill without curtailing our use of oil,  we must invest more  in ODO and import less oil on tankers.

Note that the premises tell us that oil spill risk is lower in ODOs and higher in tankers. The conclusion (which is a conditional) says that if we are to reduce the risk of oil spill, we should invest more in ODOs.
It seems perfectly reasonable conclusion, right? It says that taking only oil spill risk into account, we should use more ODOs. If I were to prethink on this, I wouldn't know how to weaken it. 
But, we can weaken it because the conclusion says "we should invest more in ODOs" and not "use more ODOs". We don't know what effect "investing more" could have on the amount of risk involved in ODO and tankers.

Then we check the options.

(A) Tankers can easily be redesigned so that their use entails less risk of an oil spill.
Now, this does weaken our conclusion. If we invest in tankers, we could easily reduce the risk. Also, now the use of the word "presently" in our premises makes sense. The premises say clearly that presently the risk with tankers is higher. So it all fits in. Yes, we don't know whether with investment, the risk with tankers will go below the risk with ODOs but it clearly raises a question and hence weakens the conclusion.

(B) Oil spills caused by tankers have generally been more serious than those caused by offshore operations.
This, if anything, strengthens our conclusion.

(C) The impact of offshore operations on the environment can be controlled by careful management.
Irrelevant. We are only considering risk of oil spill.

(D) Offshore operations usually damage the ocean floor, but tankers rarely cause such damage.
Doesn't matter what they actually damage - the ocean floor or agricultural land or underground water etc. The risk of oil spill is less with ODOs and that is all we are concerned with.

(E) Importing oil on tankers is currently less expensive than drilling for it offshore.
Irrelevant. We are only considering risk of oil spill, not cost.

Answer (A)

TomB · Answer

Offshore oil-drilling operations entail an unavoidable risk of an oil spill, but importing oil on tankers presently
entails an even greater such risk per barrel of oil. Therefore, if we are to reduce the risk of an oil spill without
curtailing our use of oil, we must invest more in offshore operations and import less oil on tankers.
Which of the following, if true, most seriously weakens the argument above?
(A) Tankers can easily be redesigned so that their use entails less risk of an oil spill.
(B) Oil spills caused by tankers have generally been more serious than those caused by offshore operations.
(C) The impact of offshore operations on the environment can be controlled by careful management.
(D) Offshore operations usually damage the ocean floor, but tankers rarely cause such damage.
(E) Importing oil on tankers is currently less expensive than drilling for it offshore
I am confused between options A & E. According to CR bible, we have to weaken the conclusion so option E seems good. But , option A weakens the premises. I dont know which one is correct. am I missing any point?plz explain. I saw this post in this forum,but nobody explained my doubt

manojmakkatt · Answer

Hello TomB,

Our primary concern over here is oil spill and not monetary benefit.
According to the author bringing oil in tanker is very risk, but If we can prove to the author there are methods to make this process risk free then we are proving him wrong and A does just that.

(A) Tankers can easily be redesigned so that their use entails less risk of an oil spill.: correct

But options D and E talk about damage to ocean flour and monetary benefit and both are irrelevant in the present context,

(D) Offshore operations usually damage the ocean floor, but tankers rarely cause such damage.
(E) Importing oil on tankers is currently less expensive than drilling for it offshore.

Other options ,

B supports author .
C is irrelevant.

Hope this helps

asimov · Answer

A

The argument is for curtailing the risk of oil spills. Only A address the risk. E does not address the argument.

GyanOne · Answer

We must choose an option that strengthens the argument that tankers, rather than offshore operations are more suitable for procuring oil without causing an oil spill.

Option (A) is the option which clearly supports this. If tankers can easily be redesigned to reduce the risk of an oil spill, then they become a more viable option to get oil while minimizing the spill risk.

Option (D) is wrong because we are not discussing damage to the ocean floor here - just the risks of an oil spill. This is therefore irrelevant to the argument.

(A) is therefore the correct option

akhil911 · Answer

Key steps to come to the answer:

1. Clearly understand the Conclusion and the premise :
Conclusion - To reduce the risk of an oil spill without curtailing our use of oil, we must invest more in offshore operations and import less oil on tankers.
Premise - Offshore oil drill operations have an unavoidable risk of oil spill but importing on oil tankers carries an even greater risk.

Think of how the conclusion is reached on the basis of the premise and what assumptions can be made.
Assumption 1 : By investing more on offshore operations risk can be reduced.

If we somehow break this assumption then that will give us the correct answer.
If some answer choice gives us that investing in Oil tankers will be easy and will reduce risk then that will be the correct answer choice and A is exactly that.
Rest all answer choices are either irrelevant or strengthening the conclusion.

Kudos me if you like the post !!!!!!!!!!!!

rsaahil90 · Answer

Hello

I have a small concern with A => The way the argument is structured, it says:
Premise: Offshore Drill Ops (ODO) are risky but importing oil tankers (IOT) entails an even greater risk per barrel
Conclusion: To be safe without limiting use, we should invest more in ODO vs. IOT

Now if we look at A i.e. "Tankers can easily be redesigned so that their use entails less risk of an oil spill" --> Here, for sure we see that the risk is diminished but since the premise and conclusion both are of the comparative nature, we must have a reason that forces us to believe that with the change in design, the risk will be lower in comparison to ODO. A simply states that the risk is lowered but we are still not sure if the redesign sufficiently helps us resolve the issue at hand (i.e. Risk for IOT<Risk for ODO)

With this, I was quite confused b/w A and D (D involves external context). Any help will be appreciated.

Thanks

KyleWiddison · Answer

I agree that it would be nice to have some idea of the degree to which the tankers can be improved, but by process of elimination A is the only option that weakens the argument to any degree. It may not destroy the conclusion, but it does absolutely weaken it. D, on the other hand, gives us information that we can't evaluate because we don't know the impact of oil on the ocean floor - maybe the best kind of oil spill is one that only impacts the ocean floor and not the surface...

KW

anairamitch1804 · Answer

This question is asking us to weaken the argument above. The argument’s conclusion is that we must invest more in offshore operations and import less oil on tankers. Why? The premise of the argument is that oil tankers currently provide a bigger risk of spilling oil per barrel of oil. The question even has the diamond in the rough word “presently”, which hints that this situation could change. Without even looking at the answer choices, we can surmise that this situation isn’t set in stone and can therefore be changed.

In other words: how do we weaken the argument above? Well, what if it simply weren’t true anymore? The whole argument hinges on tankers being more risky. So if new information or new technology allowed the tankers to become safer than their offshore counterparts, the entire argument would fall apart. Let’s sift through the answers to see if any of these match our needs:

(A) Tankers can easily be redesigned so that their use entails less risk of an oil spill.

Well this is pretty much exactly what we’re shooting for. Let’s see if any of the other choices make us reconsider this choice. (a choice that’s equivalent to Arnold’s classic: “come with me if you want to live”)

(B) Oil spills caused by tankers have generally been more serious than those caused by offshore operations.

This option is actually a 180°, as it strengthens the argument. We shouldn’t use tankers because tankers are more dangerous. Perfect strengthener. These options can be very tempting, as they are excellent answers, except for the lack of the word “not”, which is somewhat crucial in this case.

(C) The impact of offshore operations on the environment can be controlled by careful management.

Much like answer choice B, this actually strengthens the argument. At this point you might start wondering if you’re misinterpreting the question, as the majority of the choices seem to contradict your interpretation. This is a classic GMAT ploy, so don’t fall for it. This underscores again why making a prediction is crucial in these situations.

(D) Offshore operations usually damage the ocean floor, but tankers rarely cause such damage.

This argument is discussing oil spills, so whether the environmental damage is limited to the seafloor or the seashells (and whether she sells seashells by the sea shore) is irrelevant to the issue.

(E) Importing oil on tankers is currently less expensive than drilling for it offshore.

The economic argument is frequently a compelling one, especially for aspiring business students, but the focus is on the environment impact of oil spills, not whether I can get premium gas for a few cents cheaper. This is out of scope of the issue.

The correct answer is (A).

Gmat20201 · Answer

Offshore oil-drilling operations entail an unavoidable risk of an oil spill, but importing oil on tankers presently entails an even greater such risk per barrel of oil. Therefore, if we are to reduce the risk of an oil spill without curtailing our use of oil, we must invest more in offshore operations and import less oil on tankers.

Which of the following, if true, most seriously weakens the argument above.

Soln:-

My accuracy has improved solving CR questions as below:

Identify the GOAL- Read the conclusion 
Here the GOAL is to Reduce risk of oil spill

Next be clear on -->What is the recommendation/ plan to achieve it
Plan : Invest more in offshore operations and import less oil on tankers
 
With this information - we read question and it says we need to weaken the argument. Okay so lets check option and weaken the plan.

A) Tankers can easily be redesigned so that their use entails less risk of an oil spill.
- Okay at first go i did not find problem in this , it definitely weakens . So hold it and check other options.
- This option weakens the plan to invest more in offshore operations by showing an alternate way which can be easily done to achieve or fulfill the goal to reduce oil spill. Plan to reduce import through tanker is weakened with easy solution mentioned in this option.

B) Oil spills caused by tankers have generally been more serious than those caused by offshore operations.
- This definitely supports the plan and gives one more reason to invest more in offshore operations . Since it does reverse of weaken we eliminate this option

C) The impact of offshore operations on the environments can be controlled by careful management.
- Goal is to reduce risk of spill and plan is to invest more in offshore ops and reduce import through tankers. Remember this and reading option C we find it does not anyways weaken the plan. In a way it supports plan by saying that impact can be controlled. So Eliminate

D) Offshore operations usually damage the ocean floor, but tankers rarely cause such damage.
- Goal is to reduce the oil spill , no where in the argument it talks about the damage to ocean floor as concern so this choice goes beyond the scope of argument. So dont fall in trap. Focus on Goal and info given in the argument.

E) Importing oil on tankers is currently less expensive than drilling for it offshores.
- Expense is again not discussed nor the concern. Goal is to reduce oil spill not control expense. So Eliminate.

Ans choice A is Correct

Follow POE and keep goal and plan clear ( if needed write them )

Hope this helps.

vinayparkash · Answer

Option A only says it will be less risky after redesigning but whether it will still be less riskier than offshore is not hinted by option A. The option E says it's less expensive. This option is not irrelevant since you an notice in the last line the phrase "without curtailing the use of oil': If you buy expensive oil the use will be curtailed. I request  Gmat  NINJA for some insights

DmitryFarberMPrep · Answer

vinayparkash

For A), remember that we are tasked only with weakening, not disproving. Sure, we don't know how much the risk will be reduced, but we also don't know the difference in risk now. This is a very common pattern in CR questions: the argument relies some vague difference or discrepancy, and then a correct answer tells us that this difference MAY disappear or MAY not have as much of an effect in the future. That's all we need to weaken.

As for E), we can't assume that using a more expensive option would involved curtailing the use of oil. Perhaps we can still afford to use all the oil we want at that price! In general, be wary of any answer that relies on the idea that higher prices will reduce demand or usage. That's a common principle that applies in many cases, but not a reliable fact.

ADisHere · Answer

In critical reasoning, isnt weakening a plan by giving an alternate plan (like what A does) incorrect?

I plan to sell my upcoming book to pay off my tuition fees. Can't you weaken my plan by saying that no one will even publish that book?
you cant weaken this by saying selling clothes can pay off you tuition fees right?

DmitryFarberMPrep · Answer

It really depends on the nature of the argument. Sure, if I conclude that my plan X will produce result Y, then it doesn't weaken my argument to point out that there are other ways to produce result Y. Other plans don't invalidate mine. But if I claim that we  must  do my plan, then you can certainly weaken my argument by pointing out other ways to get the desired result. For instance, if I claim that you must eat potato chips because your body needs carbohydrates, salt, and fat, then clearly you can weaken my (very shaky) argument by making it clear that you can get carbohydrates, salt, and fat from other foods.

In this case, however, the correct answer isn't even providing an alternative plan. The original argument says that tankers are riskier than offshore drilling, so we  must  use them less and shift toward offshore operations. So it's attacking one method by comparing it unfavorably to another. Answer choice A is saying that we can improve the current method, so it weakens the argument that we must replace this method.

If A had talked about a third method, that could also weaken, as long as this method was described as comparatively safe. Again, since the argument says that we must invest in offshore, any suggestion of other alternatives weakens the idea that we must choose this one. That's different from weakening an argument that we  can  use offshore, but the author isn't making that milder argument.

ADisHere · Answer

Got it! So, the argument compared A and B and said B is weaker than A.
But now the answer is that B (the original plan) can be strengthened, which only slightly weakens ( not fully), and that B is not weaker than A.
It is not bringing an alternate plan by saying C (a COmpletely new thing) is better
Am I right?

DmitryFarberMPrep · Answer

Yes, exactly! It's saying that the proposed alternative (offshore) isn't necessarily safer than the adjusted tankers, so we don't necessarily have to shift more toward offshore.

VerbalBot · Answer

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Offshore oil-drilling operations entail an unavoidable risk of an oil

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Offshore oil-drilling operations entail an unavoidable risk of an oil

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