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
An apical radiolucent area present in central incisor
after 4 months of RCT is due to: 
Select and explain. 
A. Inadequate obturation & leakage from main canal, B. Leakage from accessory canal, C. Leakage from gingival crevice, D. Leakage from access opening
A: Inadequate obturation & leakage from main canal
Answer: A: Inadequate obturation & leakage from main canal 
Explanation: None