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
Saguinarine is 
Select and explain. 
A. An anti plaque agent, B. Derived from blood platelets, C. One of the antiseptic agents in chemical plaque control, D. All of the above
A: An anti plaque agent
Answer: A: An anti plaque agent 
Explanation: None