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 of the following reactions is least likely to be observed during orthodontic treatment? 
Select and explain. 
A. Root resorption, B. Devitalization of teeth that are moved, C. Mobility of teeth that are moved, D. Development of occlusal interferences
B: Devitalization of teeth that are moved
Answer: B: Devitalization of teeth that are moved 
Explanation: Root resorption is common during orthodontic treatment, although lesions often repair on the root surface. Mobility of teeth is also common as the PDL reorganizes and widens during tooth movement. It is uncommon for teeth to become devitalized as a result of orthodontic movement unless they have also been substantially compromised by injury or infection.