Ron Has Alzheimer's Disease

Ron has Alzheimer's disease. He frequently forgets doctor's appointments and almost started a fire in his kitchen because he forgot a pan on the stove. Recently, his son was concerned because Ron blamed him for stealing his car keys when Ron simply forgot where he put them. What phase of Alzheimer's disease is Ron in?

A) early phase
B) beyond the early phases and he may be unable to care for himself
C) he absolutely cannot care for himself and will need 24-hour assistance
D) final phase