Bio-chemists at Perck Pharma Corporation have discovered a new type of

To eliminate C

The key word here is Many cases. Many does not mean all.
The conclusion says - in all cases the bee is required to pollinate the flower for the allergy

Imo A
Between A and C A is better .
Moreover we have to carefully the words such as all,many and some for questions like these .

Hi jwang516,
This is a strengthen question and not an inference question.

Bio-chemists at Perck Pharma Corporation have discovered a new type of allergy. Their research confirms that not only is it caused by pollen of a certain flower, as it was thought, but also the flower has to be pollinated by a certain kind of bee to cause the allergy.

Type - strengthen
Boil it down - Allergy is caused by pollen of a certain flower, as it was thought, but also the flower has to be pollinated by a certain kind of bee to cause the allergy.
We have 2 necessary conditions to cause allergy here-
1. Pollen of the certain flower
2. Only when the flower has been pollinated a certain kind of bee


(A) In the absence of the bee, the pollen does not cause allergic reactions - Correct - If the flower was not pollinated by that particular bee, then the pollen will not cause the allergy
(B) The bee has been shown to be a critical element in the reproduction of the particular flower. - Irrelevant
(C) Many cases of the allergy have been observed only in the presence of the bee - Incorrect - we have no idea whether that pollen of that particular plant is involved here
(D) In cases in which the allergy does not develop, the flower will grow without the presence of the bee - Incorrect
(E) The onset of the allergy is usually caused by the flower even if the pollen is not present. - Incorrect - this weakens as pollen is not necessary

Answer A

Hi Skywalker18, VeritasKarishma

Got stuck between A and D.

Argument says that if the flowers are not pollinated by the specific bees the flower would not grow on to become allergic.

Option 'D' says that if the allergy has not developed that means the flower has grown with the presence of THE bee.

Won't this reason support data's implication in the argument ?

Option 'A' seemed too straight forward almost like it's stating the same thing mentioned in the argument.

Can you please explain the flaw in my reasoning ?

Many Thanks
Saurabh

Posted from my mobile device

Such questions are best explained by discussing the conditional statements framework:
https://www.gmatclub.com/forum/veritas-prep-resource-links-no-longer-available-399979.html#/2012/1 ... tatements/

The argument tells us that as per the new research, the allergy happens ONLY IF a particular bee pollinates the flower.

Note how do we establish the ONLY IF relation:
Only if A, then B (Only if "that specific bee", then "allergy")
- B implies A (allergy implies that specific bee)
- Not A implies not B (No bee means no allergy)
If both the above points are established, then we can establish the "only if" relation. (Or if the only if relation is established, then the above two points are its implications)

Option (A) gives you "no bee means no allergy". This helps in establishing the only if relation.

(D) In cases in which the allergy does not develop, the flower will grow without the presence of the bee.
Option (D) gives you "not B implies not A". This does not help us in establishing the only if relation.

Let's look at other options too:
(B) The bee has been shown to be a critical element in the reproduction of the particular flower.
Doesn't help. We want to establish that when the bee pollinates, only then the allergy happens.

(C) Many cases of the allergy have been observed only in the presence of the bee
"Many" is not good enough to establish the "only if bee, then allergy" case.

(E) The onset of the allergy is usually caused by the flower even if the pollen is not present.
This questions the already established fact - this allergy is caused by the pollen of a particular flower.

Is there difference between "only if" and "if" statements?

Previously I understood as below.
If A then B
means
Not B, not A.

Similar concept we use in "x led y".
No Y, no x.

But in case of only if A then B.
If not A, not B.


Please explain. I want to correct myself if I am wrong.

SO the question is
Allergy is caused by pollen of a certain flower and that flower has to be pollinated by a certain kind of bee to cause the allergy.

Since its an AND, both have to be present for the allergy to be present.

(A) In the absence of the bee, the pollen does not cause allergic reactions
Bee is removed, pollen wont cause allergy -> this supports the data.

(B) The bee has been shown to be a critical element in the reproduction of the particular flower.
reproduction -> OOS

(C) Many cases of the allergy have been observed only in the presence of the bee
Many cases is open ended, Allergy can or cannot happen. -> Out

(D) In cases in which the allergy does not develop, the flower will grow without the presence of the bee -> Eliminate
I was stuck here for a moment, This is a different case, not pertaining to the argument.
Here it is talking about the growth of the flower, we were concerned with its pollination by bee.
This just meant that some other bee is helping the flower to grow.

(E) The onset of the allergy is usually caused by the flower even if the pollen is not present.
This is irrelevant.

Check out this post: https://www.gmatclub.com/forum/veritas-prep-resource-links-no-longer-available-399979.html#/2012/1 ... tatements/
It talks about "if" and "only if" statements.

Thanks for sharing such a helpful link!

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