This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
Which of the following metal ions is associated with secondary Parkinsonism - 
Select and explain. 
A. Mangnese (Mn), B. Magnesium (Mg), C. Selenium (Se), D. Molybdenum (Mo)
A: Mangnese (Mn)
Answer: A: Mangnese (Mn) 
Explanation: Answer- A. Mangnese (Mn)Manganese ion exposure is implicated in free radical damage of the basal ganglia causing Parkinsonism.