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 largest permanent tooth in the mouth usually is: 
Select and explain. 
A. Maxillary canine, B. Mandibular canine, C. Mandibular first molar, D. Maxillary first molar
D: Maxillary first molar
Answer: D: Maxillary first molar 
Explanation: None