<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 39-year-old man comes to the emergency department because of fever, urinary frequency, and lower back pain for the last 3 days. During this period, he has also had pain with the 3 times he has defecated. He is sexually active with one female partner and does not use condoms. His father died of colon cancer at the age of 67 years. The patient has smoked one pack of cigarettes daily for 14 years and drinks alcohol occasionally. His temperature is 39.1C 102.3F, pulse is 114min, and blood pressure is 14090 mm Hg. Physical examination shows mild suprapubic pain on deep palpation and a swollen, tender prostate. The remainder of the examination shows no abnormalities. His hemoglobin concentration is 15.4 gdL, leukocyte count is 18,400mm3, and platelet count is 260,000mm3. Which of the following is the most appropriate next step in the management of this patients condition?? A: Perform transrectal ultrasonography, B: Measure serum prostate-specific antigen, C: Administer vancomycin, D: Urine culture, E: Administer tamsulosin,  <response>: This is a clinical vignette describing a 39-year-old man with fever, urinary symptoms, and back pain. He has risk factors for sexually transmitted infections and prostate issues. The stem asks for the most appropriate next step in management. Based on the description, the leading diagnoses include prostatitis, urinary tract infection, and sexually transmitted infections like chlamydia or gonorrhea. Imaging the prostate or checking the PSA level are not urgent next steps. The best initial test would be a urine culture to identify any bacterial infection that could be causing his symptoms. Vancomycin and tamsulosin may be appropriate treatments after a diagnosis is made, but are premature at this point.D: Urine culture 