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 root canal treatment, the canal orifices are located
by: 
Select and explain. 
A. Endodontic excavator, B. DG-16 Endodontic explorer, C. C+ file, D. H-file
B: DG-16 Endodontic explorer
Answer: B: DG-16 Endodontic explorer 
Explanation: None