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
The common preoperative causes of endodontic treatment failure include all of the following except which one? 
Select and explain. 
A. Misdiagnosis, B. Leaking coronal restoration, C. Poor case selection, D. Error in treatment planning
B: Leaking coronal restoration
Answer: B: Leaking coronal restoration 
Explanation: Failure  of  previous  endodontic  therapy  can  be  attributed  to various  factors,  such  as  procedural  errors,  missed  canals,  or persistent periapical pathosis. Knowledge of the cause of failure is pertinent to the treatment of these cases because it allows the cause to be adequately rectified.
Misdiagnosis, poor case selection and  error in treatment planning  are the preoperative causes and leaking coronal restoration is the postoperative cause of endodontic therapy failure.
Ref: Cohen pathways of Pulp 11th ed page no 44