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
Extrusive movements ideally would produce no areas of compression within PDL, but will produce: 
Select and explain. 
A. Only contusion, B. Only tension, C. Only retraction, D. Only extraction
B: Only tension
Answer: B: Only tension 
Explanation: Extrusion is defined as the axial movement of the tooth along the long axis towards the coronal part. 
Features of Extrusion:

Force required: 35–60 g
Loading pattern: No areas of compression in PDL.

Only stretched areas/tension.