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
A pronounced developmental groove is usually present on the mesial marginal ridge of a permanent: 
Select and explain. 
A. Mandibular third molar, B. Mandibular second premolar, C. Maxillary second molar, D. Maxillary first premolar
D: Maxillary first premolar
Answer: D: Maxillary first premolar 
Explanation: None