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
Which type of injury is least common in children? 
Select and explain. 
A. Intrusion, B. Avulsion, C. Subluxation, D. Complicated crown fracture
D: Complicated crown fracture
Answer: D: Complicated crown fracture 
Explanation: None