I change my answer from 'D' to 'E'
Scorer, could you elaborate the reasons for change? I would go with D.
My reasoning follows:
Brief about the statement: Alzheimer's patients have lesions caused by protein deposits. Non Alzheimer's patients have protein deposits as well (extent not mantioned in the statement). We can assume they don't have lesions though. (this is still an assumption)
Now coming to options -
(A) The statement does not describe that non-Alzheimer's sufferers have brain lesions. Doesn't hold good.
(B) Completely unrelated. (In reality though, from "external" knowledge, this is quite relevant. However since quite unrelated to the statement, we would let it go).
(C) "The technique for detection of protein is not sufficient for detection of lesions...." is a wrong statement.
(D) Suits well, if we go by the assumption we made, that though everyone had the protein deposits, only few had lesions. This could be because those few had the chemicals that led to the formation of lesions from those protein deposits. Those lesions, were the cause of Alzheimer's. This means that Alzheimer's is not related to living long enough, but to the presence of the said chemical, thus undermining the argument about "living long enough" and developing Alzherimer's.
(E) Seems quite unrelated to the whole statement about protein deposits and lesions. Even to the assertion that if everyone lives long enough he would develop Alzheimer's - since the age at which the affliction to Alzheimer's is developing is decreasing, does it mean that the age for 'living long enough" is decreasing? Can't read too much into it.
Hence I'd go for D. Of course there's a implicit assumption made here as I described above.
Any other point of view?
Who says elephants can't dance?