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: Dental
Palladium is added to polyvinyl siloxane to 
Select and explain. 
A. Act as a scavenger, B. Helps as surfactant, C. Acts as plasticizer, D. Acts as a catalyst
A: Act as a scavenger
Answer: A: Act as a scavenger 
Explanation: None