<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 60-year-old man is brought to the emergency department 25 minutes after falling and hitting his left flank on a concrete block. He has severe left-sided chest pain and mild shortness of breath. He underwent a right knee replacement surgery 2 years ago. He has type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for 42 years. Current medications include metformin, sitagliptin, and a multivitamin. He appears uncomfortable. His temperature is 37.5C 99.5F, pulse is 102min, respirations are 17min, and blood pressure is 13290 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96. Examination shows multiple abrasions on his left flank and trunk. The upper left chest wall is tender to palpation and bony crepitus is present. There are decreased breath sounds over both lung bases. Cardiac examination shows no murmurs, rubs, or gallops. The abdomen is soft and nontender. Focused assessment with sonography for trauma is negative. An x-ray of the chest shows nondisplaced fractures of the left 4th and 5th ribs, with clear lung fields bilaterally. Which of the following is the most appropriate next step in management?? A: Continuous positive airway pressure, B: Prophylactic antibiotic therapy, C: Admission and surveillance in the intensive care unit, D: Adequate analgesia and conservative management, E: Internal fixation,  <response>: This is a clinical vignette describing a 60-year-old man who fell and sustained rib fractures. He has chest pain and shortness of breath. Important history includes prior knee surgery, diabetes, and smoking. Vital signs show tachycardia but otherwise stable. Exam shows rib tenderness and decreased breath sounds. Imaging confirms nondisplaced rib fractures without other injury. The question asks for the next step in management. Choice A of CPAP is too aggressive given stable oxygenation. Choice B of antibiotics is not routinely indicated for rib fractures alone. Choice C of ICU admission is excessive given overall stable status. Choice D of analgesia and conservative management is appropriate for nondisplaced rib fractures without complications. Choice E of surgery is not indicated for nondisplaced fractures.D: Adequate analgesia and conservative management 