A 69-year-old man is brought to the clinic by his wife due to progressive difficulty walking and frequent falls over the past year. She reports that he often falls backward without warning and has developed increasing stiffness and slowness of movement. Physical examination demonstrates axial rigidity and Parkinsonism. Which of the following is the most likely diagnosis?
A) Amyotrophic lateral sclerosis
B) Lewy body dementia
C) Neuromyelitis optica
D) Progressive supranuclear palsy
E) Wilson disease
