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 single rooted tooth will most commonly have an abnormal 2nd canal 
Select and explain. 
A. Lower Canine, B. Lower First premolar, C. Lower 2nd premolar, D. Upper 1st premolar
B: Lower First premolar
Answer: B: Lower First premolar 
Explanation: None