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
Relapse after orthodontic tooth movement is due to 
Select and explain. 
A. Supracrestal gingival fibers, B. Abnormal pressure habits, C. Improper angulation of the teeth, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None