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
Palatal secretions affect the setting of all the impression materials except: 
Select and explain. 
A. Silicone, B. Agar-agar, C. Impression paste, D. Impression plaster
B: Agar-agar
Answer: B: Agar-agar 
Explanation: None