Final answer:
The most significant factor contributing to the issue in the scenario is the prisoner's physical/mental ability, as his health conditions, including disabilities and the need for seizure medication, were not properly accommodated.
Step-by-step explanation:
The factor that most contributed to the issue described in the scenario is Physical/mental ability. The prisoner's disabilities, which include torn knee ligaments, diabetes, and proneness to seizures, were key factors that led to the hardships he faced in prison, such as being placed in an upper bunk and being denied his walking cane. Additionally, the delay in receiving his seizure medication further indicates that his physical and mental health needs were not adequately met by the prison staff. Age, appearance, and race may also contribute to issues faced by individuals in the prison system, but in this scenario, the man's physical and mental health conditions are the most significant factors leading to his mistreatment.