Lofgren's disease has been observed frequently in commercially raised cattle but very rarely in chickens. Both cattle and chickens raised for meat are often fed the type of feed that transmits the virus that causes the disease. Animals infected with the virus take more than a year to develop symptoms of Lofgren's disease, however, and chickens commercially raised for meat, unlike cattle, are generally brought to market during their first year of life.

Which of the following is most strongly supported by the information provided?


A. The virus that causes Lofgren's disease cannot be transmitted to human beings by chickens.

B. There is no way to determine whether a chicken is infected with the Lofgren's disease virus before the chicken shows symptoms of the disease.

C. A failure to observe Lofgren's disease in commercial chicken populations is not good evidence that chickens are immune to the virus that causes this disease.

D. An animal that has been infected with the virus that causes Lofgren's disease but that has not developed symptoms cannot transmit the disease to an uninfected animal of the same species.

E. The feed that chickens and cattle are fed is probably not the only source of the virus that causes Lofgren's disease.

Great! All C.



Anyway there is no OA.

I think it's B.

My reasoning:

B: There is no way to determine whether a chicken is infected with the Lofgren's disease virus before the chicken shows symptoms of the disease.
=> Why the disease is rarely observed in chicken because chickens are killed before (1 year) they (majority) show any symptoms. If we had some way to determine that the chickens are infected without knowing the symptoms, then the chances are that the cattle and chickens are equally infected by this disease.

C: A failure to observe Lofgren's disease in commercial chicken populations is not good evidence that chickens are immune (safe) to the virus that causes this disease.


=> why C may not be correct (I think) because, nowhere in the passage mentioned that the chickens are IMMUNE TO the virus. It's clearly mentioned that the disease is rarely observed, that means they are not really immune to this disease.

Please correct me if I am wrong somewhere.

Hi Guys,

While we are discussing the option B and C, let's revisit the question once again...the question says:

Which of the following is most strongly supported by the information provided?
...
B: There is no way to determine whether a chicken is infected with the Lofgren's disease virus before the chicken shows symptoms of the disease.
C: A failure to observe Lofgren's disease in commercial chicken populations is not good evidence that chickens are immune to the virus that causes this disease.
...
Now if we consider option C, what it signifies is that the:
conclusion of the given argument, say Y, is: Chickens are immune to the virus that causes this disease.
and it's given evidence in the argument, say X, is: A failure to observe Lofgren's disease in commercial chicken populations
And the option C then means that X does not lead to Y.

So, for option C to be true, author must provide both coclusion - Y and evidence X in argument, whereas,
- the argument never talks about the conclusion to be Y (it can be infered only), and,
- Also you cannot consider X as an evidence (not even as an assumption) because author did say that disease can be observed rarely in chicken...the author never talked about failure to observe disease.
So, even if Y is considered as inference (as trivikram pointed out), the option C cannot be considered as true, since X is never mentioned as evidence or assumption.

Using POE, the option B then wins.

Let me know if you have some other views.

Argument (for easy reference): "Lofgren's disease has been observed frequently in commercially raised cattle but very rarely in chickens. Both cattle and chickens raised for meat are often fed the type of feed that transmits the virus that causes the disease. Animals infected with the virus take more than a year to develop symptoms of Lofgren's disease, however, and chickens commercially raised for meat, unlike cattle, are generally brought to market during their first year of life.
"

A. transmission to human beings is not covered in the stimulus, hence eliminate.
B. we don't know if any such method exists in nature, hence eliminate. (another valid reason for elimination is that this option is too extreme)
C. correct
D. we don't know if an animal not showing any symptoms of the disease can transmit it, hence eliminate
E. completely out of scope - eliminate