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
In Peck and Peck index, mesiodistal and buccolingual measurements of which of the following tooth is taken: 
Select and explain. 
A. Maxillary central incisor, B. Mandibular central incisor, C. Maxillary premolars, D. Mandibular molars
B: Mandibular central incisor
Answer: B: Mandibular central incisor 
Explanation: None