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
Painful ulcers over genitalia are caused by – 
Select and explain. 
A. Primary syphilis, B. Granuloma inguinale, C. Chancroid, D. LGV
C: Chancroid
Answer: C: Chancroid 
Explanation: None