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
Toothache relieved with cold water indicates: 
Select and explain. 
A. Acute pulpitis, B. Arterial hyperemia, C. Irreversible pulpitis, D. Venous hyperemia
C: Irreversible pulpitis
Answer: C: Irreversible pulpitis 
Explanation: None