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
Crown completion of deciduous Mandibular central incisors occur 
Select and explain. 
A. At birth, B. 1 ½ month after birth, C. 2 ½ months after birth, D. 6 months after birth
C: 2 ½ months after birth
Answer: C: 2 ½ months after birth 
Explanation: None