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: Surgery
Which cancer develops in chronic ulcer 
Select and explain. 
A. Malignant melanoma, B. Basal cell CA, C. Squamous cell CA, D. Kaposi sarcoma
C: Squamous cell CA
Answer: C: Squamous cell CA 
Explanation: Answer- C. Squamous cell CAChronic ulcer can cause squamous cell carcinoma.