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 patient complains of pain in tooth on taking hot food, the pain subsides on taking cold. Diagnosis is: 
Select and explain. 
A. Reversible pulpitis, B. Internal resorption, C. Partial pulp necrosis, D. Traumatic injury
C: Partial pulp necrosis
Answer: C: Partial pulp necrosis 
Explanation: Typically, a tooth that responds to heat application to cause pain while the pain is resolved by cold indicates partial pulp necrosis.