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
19 years male develops painless penile ulcers 9 days after sexual intercourse with a professional sex worker likely diagnosis is – 
Select and explain. 
A. Chancroid, B. Herpes, C. Chancre, D. Traumatic ulcer
C: Chancre
Answer: C: Chancre 
Explanation: Amongst the given options only chancre (syphilis) causes painless ulcer.