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 premolar would be the most likely to have a single pulp horn? 
Select and explain. 
A. Maxillary first., B. Mandibular first., C. Mandibular second., D. Maxillary second.
B: Mandibular first.
Answer: B: Mandibular first. 
Explanation: Mandibular first premolar is most likely to have a single pulp horn