<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 10-year-old girl is brought to the emergency department because of lower abdominal pain for the past 12 hours. The pain has progressively worsened and was accompanied by occasional episodes of diarrhea. She has vomited twice. Her mother has Crohn disease. Her temperature is 38.1C 100.6F, pulse is 95min, respirations are 20min, and blood pressure is 11070 mm Hg. The abdomen is soft, and there is mild tenderness to palpation in the right lower quadrant without rebound or guarding. Bowel sounds are normal. Her hemoglobin concentration is 13.0 gdL, leukocyte count is 12,800mm3, and platelet count is 345,000mm3. Urine dipstick is negative for nitrites and leukocyte esterase. Urinalysis shows 3 WBChpf and no RBCs. Which of the following is the most appropriate next step in management?? A: Ultrasound of the abdomen, B: Colonoscopy, C: CT scan of the abdomen, D: X-ray of the abdomen, E: MRI of the abdomen,  <response>: This is a case of a 10-year-old girl presenting with lower abdominal pain, diarrhea, vomiting, and fever. Important findings include right lower quadrant tenderness on exam, family history of Crohns disease, and mild leukocytosis. The question asks about the most appropriate next step in management.The choices include various imaging modalities - ultrasound, colonoscopy, CT scan, X-ray, and MRI of the abdomen. In a child with suspected appendicitis, ultrasound is the preferred initial imaging test. It is radiation-free and highly sensitive and specific for appendicitis. Colonoscopy is invasive and not indicated at this point. CT has radiation exposure and is not necessary as an initial test. X-ray has poor sensitivity for appendicitis. MRI is expensive and usually not required. Therefore, the most appropriate next step in management is an ultrasound of the abdomen to evaluate for appendicitis.A: Ultrasound of the abdomen 