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
A patient complains of looseness of dentures within two to four hours of insertion. The most likely cause is: 
Select and explain. 
A. Psychological, B. Adaptive unresponsiveness, C. Deflective occlusion, D. Unretentive denture
C: Deflective occlusion
Answer: C: Deflective occlusion 
Explanation: None