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
Technique of root canal preparation known as telescopic technique is 
Select and explain. 
A. Crown down, B. Conventional step down, C. Conventional step back, D. Step back pressure Less
C: Conventional step back
Answer: C: Conventional step back 
Explanation: None