Critical Reasoning

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 always 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. Individuals whose diets lack vitaminB1, will contract beriberi only if they have a 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. Beriberi is caused by deficiencies in a combination of B-vitamins
E. Deficiencies in the B vitamins have widely varying effects on different individuals, so that specific diseases cannot be adequately identified.

Initially picked B but IMO D


OA PLZ?

Arg: lack of defeciencies in vitamin B causes Beri beri which causes defeciency b1

Conclu: Humans lacking B1 did not contract beri beri

This is possible only if beri - beri is caused by combination of vitamin B

Hence D

D ?
beriberi is always accompanied by a deficiency of vitamin B1 -but deficiency of vitamin B1 (and only vitamin B1) does not always casue berberi. It is necessary but not sufficient

hence D.
Beriberi is caused by deficiencies in a combination of B-vitamins

OA D

It seems to me that the right answer is D

In my opinion A is the most logical one.