This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Sexually transmitted diseases, Subject name: Dental
19 year male develops painless penile ulcers 9 days after sexual intercourse with a professional sex worker likely dignosis is 
Select and explain. 
A. Chancroid, B. Herpes, C. Chancre, D. Traumatic ulcer
C: Chancre
Answer: C: Chancre 
Explanation: In chancroid the incubation period is 3_5 days . In syphilis the incubation period is9-90 days. In the primary stage there is indicated , clean, painless ulcer , which oozes serum on pressure. From illustrated synopsis of dermatology and sexually transmitted diseases neena khanna 5th edition page no 320