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
Best material for obturating a root canal of a tooth is: 
Select and explain. 
A. Thermoplastic GP, B. Silver cone, C. Resorbable paste, D. GP with sealer
D: GP with sealer
Answer: D: GP with sealer 
Explanation: None