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
Christensen's phenomenon is seen in: 
Select and explain. 
A. Hinge movement., B. Protrusive movement, C. Lateral movement., D. All of the above.
B: Protrusive movement
Answer: B: Protrusive movement 
Explanation: Protrusive movement occurs while incising and grasping food. This movement occurs after the condyles rotate for more than 13° in the TMJ. The mandible moves forwards and downwards, bringing the maxillary and mandibular anterior teeth in an edge-to-edge relation. The characteristic posterior separation seen during anterior protrusion is called 'Christensen's phenomenon.