<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 23-year-old G1P0 female presents to her OBGYN for her routine 36-week visit. Her current complaints include increased fatigue at the end of the day, and edema in her ankles. The patients physical examination is unremarkable except for inguinal adenopathy. Upon pelvic examination for cervical changes, the OBGYN notices a vaginal chancre. The patient states that it is not painful when touched. Which of the following is the most likely diagnosis?? A: Primary syphilis, B: Secondary syphilis, C: Gummatous syphilis, D: Neurosyphilis, E: Cardiovascular syphilis,  <response>: This is a medical question asking about the most likely diagnosis for a patient with symptoms of fatigue, edema, inguinal adenopathy, and a painless vaginal chancre at 36 weeks gestation. The key finding is the painless vaginal chancre, which indicates this is an infectious disease. The choices list different stages of syphilis. Primary syphilis classically presents with a painless chancre, so this is likely the correct diagnosis over the other stages of syphilis.A: Primary syphilis 