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
In the lactobacillus count test, which reading will be inferred as "Marked degree of caries activity"? 
Select and explain. 
A. >100/mL, B. >1000/mL, C. >10,000/mL, D. None of the above
C: >10,000/mL
Answer: C: >10,000/mL 
Explanation: None