<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 22-year-old man comes to the physician because of an ulcer on his penis for 12 days. The ulcer is painful and draining yellow purulent material. He returned from a study abroad trip to India 3 months ago. His immunizations are up-to-date. He is sexually active with one female partner and uses condoms inconsistently. He appears uncomfortable. His temperature is 37.2C 99.0F, pulse is 94min, and blood pressure is 12080 mm Hg. Examination shows tender inguinal lymphadenopathy. There is a 2-cm ulcer with a necrotic base proximal to the glans of the penis. Which of the following is the most likely causal organism?? A: Chlamydia trachomatis, B: Klebsiella granulomatis, C: Treponema pallidum, D: Herpes simplex virus 2, E: Haemophilus ducreyi,  <response>: This is a question about diagnosing the cause of a penile ulcer in a young sexually active man who recently returned from travel to India. The key findings are a painful ulcer on the penis draining purulent material, tender inguinal lymphadenopathy, and recent travel to India. The ulcers appearance and lymphadenopathy point towards an infectious cause rather than a malignancy or autoimmune condition. The top suspects for infectious causes of penile ulcers include:- Chlamydia trachomatis: Can cause urethritis and lymphogranuloma venereum, but ulcers are painless. So this is less likely.- Klebsiella granulomatis: Causes granuloma inguinale, which can lead to genital ulcers. But this is rare globally and not typically associated with travel.- Treponema pallidum: Causes syphilis. Painless chancre is classic, so less likely here.- Herpes simplex virus 2: Can cause painful genital ulcers, but not typically necrotic base. So less likely. - Haemophilus ducreyi: Causes chancroid, which commonly presents as a painful ulcer with purulent drainage and tender lymphadenopathy. And it is endemic in parts of Asia and Africa, so exposure during recent travel makes this organism most likely.E: Haemophilus ducreyi 