In 1992 outlaw fishing boats began illegally harvesting lobsters from

Question

In 1992 outlaw fishing boats began illegally harvesting lobsters from the territorial waters of the country of Belukia. Soon after, the annual tonnage of lobster legally harvested in Belukian waters began declining; in 1996, despite there being no reduction in the level of legal lobster fishing activity, the local catch was 9,000 tons below pre-1992 levels. It is therefore highly likely that the outlaw fishing boats harvested about 9,000 tons of lobster illegally that year.

Which of the following is an assumption on which the argument depends?

(A) The illegal lobster harvesting was not so extensive that the population of catchable lobsters in Belukia’s territorial waters had sharply declined by 1996.

(B) The average annual lobster catch, in tons, of an outlaw fishing boat has increased steadily since 1992.

(C) Outlaw fishing boats do not, as a group, harvest more lobsters than do licensed lobster-fishing boats.

(D) The annual legal lobster harvest in Belukia in 1996 was not significantly less than 9,000 tons.

(E) A significant proportion of Belukia’s operators of licensed lobster-fishing boats went out of business between 1992 and 1996.

vaibhav87 · Accepted Answer

A. The illegal lobster harvesting was not so extensive that the population of catchable lobsters in Belukia’s territorial waters had sharply declined by 1996.

Note: Cachable doesn't mean catched lobsters. Option is talking about total population from which both legal and illegal catches are executed.
So, if legal harvesters couldn't get them, who got them? That's right! --> Illegal Harvesters.

Answer Choice A is correct.

This was a tough nut for me to crack. Alternatively, I would rather solve it by elimination.

B. The average annual lobster catch, in tons, of an outlaw fishing boat has increased steadily since 1992.
Whats steadily? Like 1 ton per year? Would that be enough! NO!

C. Outlaw fishing boats do not, as a group, harvest more lobsters than do licensed lobster-fishing boats.
Again! Harvest how much more? No information!

D. The annual legal lobster harvest in Belukia in 1996 was not significantly less than 9,000 tons.
Argument is comparing the difference. Not absolute values of the catch.

E. A significant proportion of Belukia’s operators of licensed lobster-fishing boats went out of business between 1992 and 1996. I fell them, but this makes no difference.

And we are left with A.

KarishmaB · Answer

Say, Before 1992, 20,000 lobsters were harvested (completely legally) every year. In 1992, illegal harvesting started. So, 20,000 went down to 18,000. In 1996, fishing activity was the same (so same number of fishing boats for same hrs were used etc), legal catch was 9000 below 1992 levels i.e. legal catch was 11,000. Conclusion: Hence, illegal activity harvested 9000 tons that year. (to make up the initial 20,000 number) Which of the following is an assumption on which the argument depends? (A) The illegal lobster harvesting was not so extensive that the population of catchable lobsters in Belukia’s territorial waters had sharply declined by 1996. This says that the number of catchable lobsters stayed the same by 1996. So the available population of lobsters which can be caught (perhaps living above certain water level) has stayed the same. We need this to be true for our conclusion to hold. Note what happens when we negate it - the illegal harvesting WAS so extensive that the population of catchable lobsters sharply declined by 1996. If the harvesting is so extensive that the lobsters are unable to breed at the required pace to maintain the population, the number of lobsters that would be caught would be less than 20,000. Hence, illegal activity would not have harvested 9000 tons that year. (B) The average annual lobster catch, in tons, of an outlaw fishing boat has increased steadily since 1992. We need to make no assumption about one outlaw fishing boat. Perhaps many new outlaw fishing boats join every year. (C) Outlaw fishing boats do not, as a group, harvest more lobsters than do licensed lobster-fishing boats. Again, no such information is given. We don't know the comparative numbers and our conclusion does not depend on them. (D) The annual legal lobster harvest in Belukia in 1996 was not significantly less than 9,000 tons. Again, we don't know the comparative numbers and our conclusion does not depend on them. (E) A significant proportion of Belukia’s operators of licensed lobster-fishing boats went out of business between 1992 and 1996. Not given. Perhaps the annual harvest of each boat reduced by some percentage but nobody went out of business. Answer (A) Discussion on Assumption Questions: https://youtu.be/O0ROJfljRLU A Hard Assumption Question: https://youtu.be/0j4tovGifIg

RaviChandra · Answer

It should be A

A states that the Quantity of Fishes is more or less the same in 92 & 96. 
This assumption is really required.

Indien · Answer

A is the best; it emphasizes that the A(the legal catch)+B(illegal catch)= A(legal catch in 1992)+B(legal catch in 1992) only if B did not decrease because of overfishing by 1997.

I had D as a contender as well, but eliminated it after reading A. Moreover, the illegal catch does not contribute to the country's annual output (hopefully !!!)

dimitri92 · Answer

Premise: illegal lobster harvesting began in 1992.
Premise: legal catch was 9k tons below pre-1992 levels.
Conclusion: it is highly likely that illegal harvest was about 9k tons.

A defends the conclusion by eliminating the possibility that lobster population may have decreased because of rampant harvesting

since assumption strengthens the conclusion .. its logical negative should weaken the conclusion

logical negative of A:  illegal harvest was so extensive that lobster population sharply declined.

the logical negative clearly weakens the conclusion .. and passes the test

A is correct

GyanOne · Answer

The argument says that the lobster catch in 1996 was 9,000 tonnes below pre-1992 levels. It also says that the 9,000 tonnes were accounted for by illegal lobster harvesting.

Therefore any assumption that the argument depends on must propose a rejected alternative explanation for the 9,000 tonnes.

A) This seems like the alternative explanation that was rejected. If the lobster catch had not declined due to illegal harvesting done earlier, then it could have declined due to illegal harvesting done now.

A) it is.

Archit143 · Answer

Superb question , To answer this, full proof reading of the argument is reqd.

despite there being no reduction in the level of legal lobster fishing activity  , the local catch was 9,000 tons below pre-1992 levels. It is therefore highly likely that the outlaw fishing boats harvested about 9,000 tons of lobster illegally that year.

The highlighted part of the argument implies that despite extensive legal lobster harvesting the number fell only to 9000, that means the author was expecting it to fall by a huge margin.......Hence, the illegal harvesters did not do much damage to the lobsters population, that is the reason, why, even after extensive harvesting the number fell just to 9000

Hence the answer must be A!!!

Consider Kudos if my post helps!!!

Archit

kinjiGC · Answer

A. The illegal lobster harvesting was not so extensive that the population of catchable lobsters in Belukia’s territorial waters had sharply declined by 1996.
If this is negated, the argument falls apart - Hence A) If it has declined the argument that the gap of annual catch between 1992 and 1996 can be attributed to illegal catch.

B. The average annual lobster catch, in tons, of an outlaw fishing boat has increased steadily since 1992. -Out of scope as we are talking about the 1996 illegal catching of lobsters.

C. Outlaw fishing boats do not, as a group, harvest more lobsters than do licensed lobster-fishing boats. - We are not comparing the legal and illegal catch

D. The annual legal lobster harvest in Belukia in 1996 was not significantly less than 9,000 tons. - Lets say it is 4k tons. The argument doesn't break or support the argument.

E. A significant proportion of Belukia’s operators of licensed lobster-fishing boats went out of business between 1992 and 1996. - it doesn't affect the argument as per the premise - "despite there being no reduction in the level of legal lobster fishing activity"

I pick A)

Nhung · Answer

The conclusion of the argument is that the outlaw fishing boats are highly likely to harvest about 9,000 tons of lobsters in Belukian waters in 1996. 
The basis for this claim is that:
1. In 1992, outlaw fishing boats started to harvest lobsters in this area
2. After that, the annual volume harvested of lobsters declined.
3. In 1996, the annual volume harvested of legal fishing boats declined by 9,000 tons in comparison to the pre-1992 levels.
4. In 1996, the legal fishing activity is not reduced.
Then the writer must assume that the total volume of lobsters which can be harvested in 1996 is about the same as in pre-1992. 
A - CORRECT. If it's true, then there is another reason why the level of lobsters harvested by the legal fishing boats have declined by 9,000. 
B - This has no impact on the conclusion. 
C - This has no impact on the conclusion.
D - Not relevant
E - Out of scope.

swanidhi · Answer

A. The illegal lobster harvesting was not so extensive that the population of   catchable     lobsters in Belukia’s territorial waters had sharply declined by 1996.

Note  : Cachable doesn't mean catched lobsters. Option is talking about total population from which both legal and illegal catches are executed.
So, if legal harvesters couldn't get them, who got them? That's right! --> Illegal Harvesters.

Answer Choice A is correct.

This was a tough nut for me to crack. Alternatively, I would rather solve it by elimination.

B. The average annual lobster catch, in tons, of an outlaw fishing boat has increased steadily since 1992.
   Whats steadily? Like 1 ton per year? Would that be enough! NO!

C. Outlaw fishing boats do not, as a group, harvest more lobsters than do licensed lobster-fishing boats.
   Again! Harvest how much more? No information!

D. The annual legal lobster harvest in Belukia in 1996 was not significantly less than 9,000 tons. 
  Argument is comparing the difference. Not absolute values of the catch .

E. A significant proportion of Belukia’s operators of licensed lobster-fishing boats went out of business between 1992 and 1996.   I fell them, but this makes no difference.

And we are left with A.

Gau0809 · Answer

Hi @Egmat@

Although I selected the Choice A, as this is the only option that I found alright, I am not able to understand the argument AT ALL.
Please somebody help me understand the argument.
Does it mean that

Before 1992......> Total local catch = legal catch
1992-------------> local catch = illegal +legal
1996................> same

then in 1996, the legal catch was same, total local catch was below 1992 levels by 9000. 
so, in 1996, illegal catch must be 9000.
So....if we say that x is the legal catch which has not changed, in 1992, catch was 18000+x...
so what next?? I am lost..

SVaidyaraman · Answer

Fact:in 1996, despite there being no reduction in the level of legal lobster fishing activity, the local catch was 9,000 tons below pre-1992 levels.

Missing Information: 9000 tons less of legal harvesting was not due to reason other than illegal harvesting in 1996.
 
Conclusion:It is therefore highly likely that the outlaw fishing boats harvested about 9,000 tons of lobster illegally that year.

Choice A best matches the missing information.

gmatexam439 · Answer

Hello,
I am still not able to understand how can "A" be an assumption. All the explanations given till now are as if the people knew the OA and are just trying to prove that A is correct. No one has been able to give a logical reasoning. 
Please help with this one by providing a step by step break up of the argument and then how "A" is the OA.
Awaiting a quick response.
Regards

septwibowo · Answer

This is tough question, and OE has given me some light. Premise : 1. 1992 start ILLEGAL, so LEGAL catch began declining. 2. In 1996, no reduction of legal activity, but the number decline 9.000 tons. Conclusion : ILLEGAL must catch 9.000 tons. Key from OE is: how can one infer specific number (9.000 ton)? After reading this key from OE, I got some enlightenment. (A) The illegal lobster harvesting was not so extensive that the population of catchable lobsters in Belukia’s territorial waters had sharply declined by 1996. Try to negate : If population SHARPLY declined, specific conclusion about 9.000 ton cannot be inferred. BANG! (B) The average annual lobster catch, in tons, of an outlaw fishing boat has increased steadily since 1992. If increased steadily, how can one infer 9.000 ton? Btw, this was my first answer

Hope it helps.

lichting · Answer

Can any one please help me clarify this? Is it supposed to be " despite there being no increase in the level of legal lobster fishing activity, the local catch was 9000 tons below pre-1992 levels" ?
i don't understand the quoted part above

GMATNinja · Answer

The sentence is correct as is. Levels of LEGAL lobster fishing activity did not decrease. Even though legal fishing  activity  did not decrease, the actual amount of lobster  caught  legally (i.e. the output of that legal fishing activity) did decrease. So there was no decrease in the amount of lobster  fishing activity  (for example, the total number of hours spent fishing), but there WAS a decrease in the amount of lobster  caught  (the local catch in 1996 was 9,000 tons less than pre-1992 levels).

I hope that helps!

rashedBhai · Answer

if I negate (A), how does it destroy argument? Please healp  VeritasKarishma   Abhishek009

Posted from my mobile device

mSKR · Answer

OFFICIAL ANSWER EXPLANATION:

Reasoning What must be true in order for the given information to justify the conclusion that the outlaw fishing boats harvested about 9,000 tons of lobster in 1996? The argument is that since the legal catch was 9,000 tons lower in 1996 than the total annual catch was before 1992, even though the level of legal lobster activity did not decline, the illegal catch in 1996 must have been about 9,000 tons. Despite the fact that the conclusion says about 9,000 tons, this is still a rather specific number. How can such a specific number be inferred? The argument must be assuming that the total annual catch was roughly the same in 1996 as it had been before 1992. Furthermore, there would be no justification for inferring such a specific number regarding the illegal lobster catch, unless the argument assumed that the number of catchable lobsters in 1996 was not dramatically different from the number in 1992, since the level of illegal lobster activity was not known (as appears to be the case, since the argument is intended to make an inference related to that level of activity). Consider the answer choices and find one that expresses or follows from the assumption.

A Correct. If illegal lobster harvesting had been so extensive that the population of catchable lobsters in Belukia’s territorial waters had sharply declined by 1996, then the number of catchable lobsters would have been dramatically different that year from what it had been in 1992, and it would be impossible to infer, from the premises given, such a specific number as is given in the conclusion.
B The argument does not discuss how many lobsters have been caught illegally each year since 1992, but rather how many were caught in 1996 specifically.
C Whether the illegal catch in 1996 was higher or lower than the legal catch, it still could have been 9,000 tons.
D The annual legal catch before 1992 could not have been less than 9,000 tons, but the legal catch in 1996 could have been.
E The argument says there was no reduction in the amount of legal lobster activity. Therefore, it does not assume that any lobster boats went out of business.

TAKAYUKI · Answer

"had sharply declined by 1996." sounds like the population had already declined in 1996 and it doesn't logically match the former part of the sentence "The illegal lobster harvesting was not so extensive that".

For me it sound like "The illegal activity was not so extensive BUT the population sharply declined".
I think logically correct sentence should be as follows.
"The illegal lobster harvesting was not so extensive that the population of catchable lobsters in Belukia's territorial waters HADN'T sharply declined by 1996."

Could somebody tell my why this sentence can mean the population of catchable lobsters was as same as in 1992 in 1996?

In 1992 outlaw fishing boats began illegally harvesting lobsters from

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In 1992 outlaw fishing boats began illegally harvesting lobsters from

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