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
Which teeth the proximal aspect shows rhomboidal appearance: 
Select and explain. 
A. Maxillary posteriors, B. Mandibular posteriors, C. Maxillary anteriors, D. Mandibular anteriors
B: Mandibular posteriors
Answer: B: Mandibular posteriors 
Explanation: None