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
Plaque differs from materia alba in 
Select and explain. 
A. Presence of bacteria, B. Presence of glycoprotein, C. Presence of saliva, D. Absence of glycoprotein
B: Presence of glycoprotein
Answer: B: Presence of glycoprotein 
Explanation: None