Outbreaks of Rift Valley fever occur irregularly in East Africa, sever

Its E. "Recently published research has shown that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever."

This research can predict when a Rift Valley fever will break out and give more than a month's warning in advance. ("It is too expensive for farmers to use routinely, and since it is not effective until a month after vaccination")

I suspect we can argue about this one till the cows come home. The main assertion is : "experts predict that use of the vaccine will increase significantly within the next few years.
Which of the following, if true, provides the strongest justification for the experts’ prediction?" . Note NEXT FEW YEARS. This is why I deemed A incorrect. A does not provide any support for the next few years. A has been happening forever, so why all of a sudden in the next few years the vaccine demand will grow ? because of new research as described in E.

What is the source of this question ?

This is an "explain the discrepancy" question (or as I sometimes call them, "explain the surprise"):

PREMISE 1: RVF vaccine too expensive to use all the time (more expensive than damage caused)
PREMISE 2: RVF vaccine needs to be used 1 mo+ before outbreak occurs
EXPECTATION: RVF vaccine will not be used
SURPRISE: RVF vaccine will be used soon anyway

Our task: Figure out how the premises AND the surprise could all be true at once. To do that, we need a way to predict the outbreak (Premise 1), and to do so at least 1 month in advance (Premise 2). (E) demonstrates very nicely how this is possible, touching on both premises, and also noting that the study is recent thereby explaining why we didn't figure this out before. (D) is a sad story, but doesn't tell us how these farmers could afford the vaccine OR how they could predict an outbreak, so it doesn't connect to either premise.

Level is probably about a 500-600.

Outbreaks of Rift Valley fever occur irregularly in East Africa, several years apart.

Ok this is a fact. Outbraks can occur every 4 years as well as after 10 years

When outbreaks do occur, they kill thousands of cattle.

Ok. A fact, 1000 cows will die

A livestock vaccine against the disease exists but is rarely used.

The vaccine ir rarely use. Unitll now we do not know why is not used

It is too expensive for farmers to use routinely, and since it is not effective until a month after vaccination, administering it after an outbreak begins helps very little.

The vaccine has costs and is better use before an outbreak

Nevertheless, experts predict that use of the vaccine will increase significantly within the next few years.

here is something that is weird: basically the argument says that the vaccine is unuseful but its use will increase over time. We need something that explain clearly THAT

Which of the following, if true, provides the strongest justification for the experts’ prediction?

A. Rift Valley fever is spread by mosquitoes, but each outbreak is so widespread that it is impractical to control it by using insecticides.

Who carrier the outbreal is irrelevant. It doen't explain WHY there will be an increase in the use of the vaccine

B. When an outbreak of Rift Valley fever occurs, unaffected countries often refuse to import livestock from the countries affected by the outbreak.

What the other country do is not so relevant for our discrepancy

C. It would take less than a month for producers of the vaccine to adjust their production operations to cope with a large increase in demand.

Production and demand is completely irrelevant here.

D. Many cattle farmers in East Africa are nomadic or live in remote villages, and such farmers, who have little access to modern veterinary medicine, are particularly hard hit by outbreaks of Rift Valley fever.

This seems to me a statistic rather a good explanation why we will use more vaccine inthe next future. Doesn't seem good as option


E. Recently published research has shown that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever.

OKKKK. A research (so something that is reliable) sayas a prediction. So if this is true (and we know that is true because we cannot disprove the information given) we will have an increase in the use of the vaccine as prevention

E is the answer

Yeah, the wording is especially designed to cause confusion . But option E is correct.

You would generally say
storms follow humid conditions
than
humid conditions are followed by storms. Both are correct though second one is wordy.

Option E says, identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever.

Outbreaks of Rift Valley fever occur irregularly in East Africa, several years apart. When outbreaks do occur, they kill thousands of cattle. A livestock vaccine against the disease exists but is rarely used. It is too expensive for farmers to use routinely, and since it is not effective until a month after vaccination, administering it after an outbreak begins helps very little. Nevertheless, experts predict that use of the vaccine will increase significantly within the next few years.

Which of the following, if true, provides the strongest justification for the experts' prediction?

The reason why the vaccine is rarely used because
1) Expensive
2) Not effective till one month
3) Administrating after the outbreak doesn't add any value.

We need to find out a option which solves one of these problems.

A. Rift Valley fever is spread by mosquitoes, but each outbreak is so widespread that it is impractical to control it by using insecticides.-> Doesn't add any value for any of the reason.

B. When an outbreak of Rift Valley fever occurs, unaffected countries often refuse to import livestock from the countries affected by the outbreak -> Same issue as option A)

C. It would take less than a month for producers of the vaccine to adjust their production operations to cope with a large increase in demand -> Doesn't add any value

D. Many cattle farmers in East Africa are nomadic or live in remote villages, and such farmers, who have little access to modern veterinary medicine, are particularly hard hit by outbreaks of Rift Valley fever -> Doesn't add any value

E. Recently published research has shown that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever.
-> This option gives a way to to predict that outbreak is going to occur so this option solves the problem # 3 and hence the correct answer.

There are two reasons that the vaccine is not used:
1. Expensive
2. Not effective till one month of administering
The experts predict that in spite of the above two reasons, the vaccine would be used. Why?

The correct option should address any/both of the above two issues, i.e. it would suggest that the price would come down and/or that the vaccine can be administered at least one month before the onset of the outbreak.

Only Option E adresses one of these two issues, viz., the second issue. Hence E is the right answer.

(If you are unable to eliminate the other options using the logic described above, please write back again stating which other option do you think adresses one of the two issues.)

The experts' predication is "that use of the vaccine will increase significantly within the next few years"

We know that the vaccine is exists, so why not administer the vaccine routinely to avoid infections? - because "it is too expensive for farmers to use routinely"

Why not just administer the vaccine once an outbreak starts? Doing so would help very little because the vaccine is not effective until a month after vaccination.

Given these reasons explaining why the vaccine is rarely used, why do experts predict that its use will increase significantly within the next few years?


This information does not help explain why the use of the vaccine might increase significantly within the next few years, so (D) can be eliminated.

I hope this helps!

Conclusion: Experts predict that the use of the vaccine will increase significantly within the next years?
Why isn't it heavily used now? What are the potential barriers limiting it's use?
Premise 1: It's expensive
Premise 2: It's "not effective until a month after vaccination" so is there any real use for it now if it can't be timed properly?

Pre-think - what can potentially eliminate barriers to use? Experts must know something for them to conclude the way they have.

POE
(A) Rift Valley fever is spread by mosquitoes, but each outbreak is so widespread that it is impractical to control it by using insecticides.
Irrelevant to the argument.

(B) When an outbreak of Rift Valley fever occurs, unaffected countries often refuse to import livestock from the countries affected by the outbreak.
Irrelevant to the argument.

(C) It would take less than a month for producers of the vaccine to adjust their production operations to cope with a large increase in demand.
Careful. This is a Shell game resposne. The question maker is using details from the passage to lure you into thinking this is right.
Just because it takes <1 month to adjust production to deal with large increases in demand doesn't mean we can predict when the disease will break out. The relevance is that the disease takes 1 month to show signs of it's presence, so this question is shelling around the "1 month" detail.

(D) Many cattle farmers in East Africa are nomadic or live in remote villages, and such farmers, who have little access to modern veterinary medicine, are particularly hard hit by outbreaks of Rift Valley fever.
Irrelevant fact to our argument.

(E) Recently published research has shown that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever.
Careful on the wording of this. Read is slowly.
"certain identifiable conditions are almost invariably followed...by an outbreak of rift valley fever (within 2 - 5 months)" - thus we can prevent the outbreak occuring if we know when it'll occur.

Strengthens.

How is Option E the correct answer ? Does it not mean that the climatic conditions happen after the outbreak ? So how can one predict ? You can predict based on the climatic conditions if the climate conditions occurred before the outbreak in that case yes the farmers could predict and give the cattle the vaccine as a precaution.

Take another look at the exact wording of (E):

This tells us that certain climatic conditions are followed by an outbreak of Rift Valley fever. So yes, the farmers can predict a future outbreak when these particular climatic conditions occur. And because there is a convenient two to five month gap between the climatic conditions and the potential epidemic, the farmers can administer the vaccine in time for their cattle to have immunity before the outbreak occurs.

The vaccine is "too expensive for farmers to use routinely," but with the information in answer choice (E), farmers can predict an oncoming outbreak and use the vaccine only when it is needed. This supports the experts' prediction that " use of the vaccine will increase significantly within the next few years." (E) is the correct choice.

I hope that helps!

Hi GMATNinja - I was confused just like mimajit on the option e.

So just so I am clear this sentence " E) Recently published research has shown that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever." means that first the climatic conditions change and after that there is an outbreak of the fever. Right?

Take a look at this post and let me know if you have any further questions.

I hope that helps!

Let’s look at the argument given-

Premises-
Outbreaks of Rift Valley fever occur irregularly in East Africa, several years apart.
When outbreaks do occur, they kill thousands of cattle.
A livestock vaccine against the disease exists but is rarely used.
It is too expensive for farmers to use routinely, and since it is not effective until a month after vaccination, administering it after an outbreak begins helps very little.

Expert’s Prediction
Nevertheless,
experts predict that the use of the vaccine will increase significantly within the next few years.

We need to look for an option that provides the strongest justification for the experts' prediction


(A) Rift Valley fever is spread by mosquitoes, but each outbreak is so widespread that it is impractical to control it by using insecticides.
The fact that we cannot control the fever by using insecticides does not justifiy how the use of the vaccine will increase significantly within the next few years. The problems stated in the premise still hold. Eliminate.

(B) When an outbreak of Rift Valley fever occurs, unaffected countries often refuse to import livestock from the countries affected by the outbreak.
Not relevant. Eliminate.

(C) It would take less than a month for producers of the vaccine to adjust their production operations to cope with a large increase in demand.
But will there be an increase in demand? Not sure. Eliminate.

(D) Many cattle farmers in East Africa are nomadic or live in remote villages, and such farmers, who have little access to modern veterinary medicine, are particularly hard hit by outbreaks of Rift Valley fever.
This does not justify how the use of vaccines will increase, considering the problems stated. Eliminate.

(E) Recently published research has shown that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever.
A recently published article shows that certain identifiable climatic conditions are almost invariably followed, within two to five months, by an outbreak of Rift Valley fever.
Identifiable climatic conditions will help farmers know when to use the vaccine. This takes care of the problem stated- that the farmers have to use it routinely.
Option E justifies how the use of vaccines will increase in the next few years. Correct.

Vishnupriya
GMAT Verbal SME

Is this question actually a 500-600 level question? Where/when would this question start showing up? I can’t actually believe this is only a 500-600 level question

Posted from my mobile device

You can check difficulty level of a question along with the stats on it in the first post. For this question Difficulty: 700, not Sub-600 Level. The difficulty level of a question is calculated automatically based on the timer stats from the users which attempted the question.

It was a pretty straight forward question for that matter it was asking us to find an option that would help us in identifying whether the vaccine will be ad/ministrated definitely E provides a very natural answer that if there would be a outbreak and the vaccines has to be administrated a month before the only option that stands out is E