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
Among the following first teeth to erupt in the oral cavity is: 
Select and explain. 
A. Maxillary central incisor, B. Mandibular central incisor., C. Maxillary lateral incisor., D. Mandibular lateral incisor.
B: Mandibular central incisor.
Answer: B: Mandibular central incisor. 
Explanation: Eruption timing for
Mandibular central incisor: 6 yrs.
Mandibular lateral incisor and maxillary central incisor: 7-8 yrs.
Maxillary lateral incisor: 8-9 yrs.