As mr. b enters the room, you observe that his gait is wide-based and he staggers from side to side while swaying his trunk. you would document mr. b's pattern as:

I believe the answer is: cerebellar ataxia.

cerebellar ataxia is a form of disorder that make the patient unable to create proper muscle movement/coordination.  The most likely cause of this disorder is the damage or inflammation that exist within the Cerebellum are of the patient's brain.