This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Raised ICP and Brain death, Subject name: Medicine
A 65-year-old man presents to your clinic after falling several times in the past few months. On examination, his most notable findings are an unstable, wide-based gait and marked retropulsion. He does have bradykinesia with masked facies and dysahria. You find no evidence of cogwheeling or resting tremor. His symptoms do not respond to levodopa/carbidopa. During the next few months, his eye movements are notable for the slowing of veical saccades and fast phases. What is the most likely diagnosis? 
Select and explain. 
A. L-DOPA resistant PD, B. Progressive supranuclear gaze palsy, C. Multiple system atrophy, D. Foville syndrome
B: Progressive supranuclear gaze palsy
Answer: B: Progressive supranuclear gaze palsy 
Explanation: Option A - Ruled out as resting tremors are absent & disease is ruled out as it is a ATYPICAL PARKINSONISM disease. Option B- since in the question its mentioned regarding the veical gaze of the patient, it's the most appropriate option. Option C- Ruled out as autonomic insufficiency isn't mentioned in the question. Option D- Manifestation of STROKE related to Pons with VIth nerve palsy.