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: Pathology
painful crater like 1.5 cm ulcer develops within one week on the hard palate mucosa of a 40 year old female. The most likely diagnosis is: 
Select and explain. 
A. Actinomycosis, B. Squamous cell carcinoma, C. Pleomorphic adenoma, D. Necrotizing sialometaplasia
D: Necrotizing sialometaplasia
Answer: D: Necrotizing sialometaplasia 
Explanation: None