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
What is the functional form of anterior teeth from the mesial or the distal aspect? 
Select and explain. 
A. Rhomboidal, B. Trapezoidal, C. Elliptical, D. Wedge-shaped
D: Wedge-shaped
Answer: D: Wedge-shaped 
Explanation: None