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
Maximum number of developmental grooves are present on the cingulum of: 
Select and explain. 
A. Permanent maxillary lateral incisor., B. Permanent mandibular central incisor., C. Permanent maxillary canine., D. Permanent mandibular lateral incisors.
B: Permanent mandibular central incisor.
Answer: B: Permanent mandibular central incisor. 
Explanation: None