<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 13-year-old African-American boy is brought to the physician because of a 4-week history of left groin and buttock pain. The pain is worse with activity but also present at rest. He has had many episodes of abdominal, back, and chest pain that required hospitalization in the past. He is at the 20th percentile for height and 25th percentile for weight. His temperature is 36.7C 98F, blood pressure is 11582 mm Hg, and pulse is 84min. Examination shows tenderness over the lateral aspect of the left hip with no swelling, warmth, or erythema. There is pain with passive abduction and internal rotation of the left hip. Leukocyte count is 8,600mm3. Which of the following is the most likely cause of this patients symptoms?? A: Septic arthritis, B: Proximal femoral osteosarcoma, C: Avascular necrosis, D: Transient synovitis, E: Impaired skeletal growthn,  <response>: This is a clinical vignette about a 13-year-old African American boy with left hip and buttock pain that has been present for 4 weeks. The key findings are:- Left groin and buttock pain worse with activity and present at rest - History of recurrent abdominal, back and chest pain requiring hospitalization- Below average height and weight percentiles - Tenderness over lateral left hip, pain with passive abduction and internal rotation- Normal temperature, mild hypertension, normal pulse, normal WBC countThe differential diagnosis includes septic arthritis, osteosarcoma, avascular necrosis, transient synovitis and impaired skeletal growth. However, the chronicity, recurrent pain episodes, normal WBC count and lack of warmth or swelling make septic arthritis very unlikely. Osteosarcoma would be rare in a 13 year old and there is no mention of a mass. Impaired skeletal growth could contribute but would not explain the acute hip pain. The presentation is most consistent with avascular necrosis, which can cause hip pain and occur in the setting of recurrent pain episodes requiring hospitalization. Transient synovitis is also a consideration given the patients age, but avascular necrosis fits the clinical picture better.C: Avascular necrosis 