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
Proper lip support for complete denture is provided primarily by: 
Select and explain. 
A. Convex surface of labial flange, B. Facial surface of teeth and simulated gingiva, C. Thickness of border in the vestibule, D. Festooned carvings on facial surface
B: Facial surface of teeth and simulated gingiva
Answer: B: Facial surface of teeth and simulated gingiva 
Explanation: Proclination of maxillary anterior teeth and the surrounding denture base simulating the gingiva provided for the bulk for lip support in complete denture.