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
Radiopaque irregularity associated with the roots of mandibular central incisors most likely represent? 
Select and explain. 
A. Root Caries, B. Subgingival Calculus, C. Subgingival Pellicle, D. Hyperplastic Cementum
B: Subgingival Calculus
Answer: B: Subgingival Calculus 
Explanation: None