It is difficult to find the precise causes of any disease

Question

It is difficult to find the precise causes of any disease resulting from B-vitamin deficiencies. For example, it was known that being deficient in all the B-vitamins was sufficient to contract the disease beriberi, and also that beriberi was alwasy accompanied by a deficiency of vitamin B1. However, recent human volunteers on special diets designed to lack only vitamin B1 did not contract the disease.

Which of the following if true best explains the results above?

A) Inviduals whose diet lack vitamin B1 will contract beriberi only if they have generally unhealthy diet.
B) A deficiency in vitamin B1 is not necessary to contract beriberi
C) Beriberi can be cured by any variety of B-vitamin supplements
D) Berberi is caused by deficiencies in a combination of B-vitamins
E) Deficiencies in B-vitamins have widely varying effects on different individuals, so that specific diseases cannot be adequately identified

gayathri · Answer

Please explain your choice...

vprabhala · Answer

D) Berberi is caused by deficiencies in a combination of B-vitamins 
  For example, it was known that being deficient in all the B-vitamins was sufficient to contract the disease beriberi, and also that beriberi was alwasy accompanied by a deficiency of vitamin B1 

says that its for sure some kind of Vitamin B deficiency and the last statement says that people lacking in Vitamin B1 didn't contract it. .that means it needs a combination of Vitamn B..

rthothad · Answer

There are 2 premises of interest:
1. It was known that being deficient in all the B-vitamins was sufficient to contract the disease beriberi.
2. Beriberi was always accompanied by a deficiency of vitamin B1 

When volunteers where put on a diet that lacked only in Vitamin B1 they did not contract Beriberi meaning that premise 2 is not always true. So, from premise 1 we can conclude that 'D' would be true.

FN · Answer

B, i think the first line in the passage says it all...hard to say vitamin B defecencies causes X disease!

though after re-reading the passage D looks good too..I mean the passage initially say all B vitamins, but then changes the foucs to B1...on exam day I might pick D, but for now .... 

i go with B

whats OA?

gayathri · Answer

OA is D.

Can someone explain why it cannot be B?

banerjeea_98 · Answer

D for me.

Wud have chosen B if it had said something like "Deficient ONLY in vitamin B1 is not necessary for the disease". This is something the stem says directly, but it also says that lacking ONLY B1 in an otherwise healthy diet. Lacking in B1 in addition to other vitamins may cause the disease.

aurobindo · Answer

I think the answer is D, as the evidence is conflicting. D can't be proven wrong. But B can be with the example cited above in the argument.

cangetgmat · Answer

can someone explain the difference between B and D

kraizada84 · Answer

beriberi--> B1 deficiency 
so B1 deficiency may or may not --> beriberi

actually what option B does here is that it simply states the above logic and does nothing to add on to something we may need to answer the required question.

Whereas option D does provides us with a solid information to explain the study results.

Hence D is the correct one.

Hope this helps..!!

It is difficult to find the precise causes of any disease

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