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
Undersurface of pontic should be 
Select and explain. 
A. Concave mesio distally and convex buccolingually, B. Convex mesio distally and concave buccolingually, C. Convex in all directions, D. Concave in all directions
B: Convex mesio distally and concave buccolingually
Answer: B: Convex mesio distally and concave buccolingually 
Explanation: None