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
Snyder's test tell us the: 
Select and explain. 
A. Exact nature of microorganisms, B. Combined acidogenic nature of microorganisms, C. Enamel dissolving capacity of saliva, D. All of the above
B: Combined acidogenic nature of microorganisms
Answer: B: Combined acidogenic nature of microorganisms 
Explanation: None