Step 1: The question asks which statement is FALSE about Alzheimer's disease, so test each option.
Step 2: Alzheimer's is a progressive neurodegenerative disease and the most common cause of dementia, so option (c) is true. Its prevalence rises sharply with age, and the figure of about one in ten people aged 65 and older having Alzheimer's is an accepted statistic, so option (a) is true.
Step 3: There is currently NO cure for Alzheimer's. Available drugs (cholinesterase inhibitors like donepezil, rivastigmine, galantamine, and memantine) only ease symptoms for a time and do not stop or reverse disease progression. So the statement that it is curable (b) is false.
Step 4: Because (a) and (c) are true, the all of the above option (d) cannot be the false one. The single false statement is (b).