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
Although standarize technique is simple and rapid but not used frequently because: 
Select and explain. 
A. Inaccurate technique., B. Relies on inherent shape of file to give shape of canal., C. Accessory canals are not removed efficiently., D. All of the above.
B: Relies on inherent shape of file to give shape of canal.
Answer: B: Relies on inherent shape of file to give shape of canal. 
Explanation: None