【单选题】The symptoms of Alzheimer's disease were long dismissed as normal consequences of human aging, but in the 1980's the disease came to be recognized as the most common cause of intellectual deterioratio...
A.
In the past, Alzheimer's disease has often been mistaken as normal human aging.
B.
Victims of Alzheimer's disease rarely need to he institutionalized.
C.
There is currently no cure for Alzheimer's disease.
D.
The primary symptoms are serious forgetfulness and confusion.
【单选题】In' The major debilitating symptoms of Alzheimer's disease include serous forgetfulness -- particularly about recent events-- and confusion.', ' debilitating' means ______.