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
Hot tooth is: 
Select and explain. 
A. Tooth in line of fracture, B. Difficult to anesthetise, C. Vertical line fracture, D. Very sensitive to heat test
B: Difficult to anesthetise
Answer: B: Difficult to anesthetise 
Explanation: A tooth that is difficult to anesthetize is known as a “hot tooth”. 
This is most commonly encountered in a mandibular first molar tooth wherein after the anesthetic block, the patient may describe profound numbness of the ipsilateral lip and tongue but still may experience acute pain during the access opening procedure.

Ref: Grossman’s endodontics, 13th edition, pg no:149