<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A previously healthy 2-year-old boy is brought to the emergency room by his mother because of persistent crying and refusal to move his right arm. The episode began 30 minutes ago after the mother lifted him up by the arms. He appears distressed and is inconsolable. On examination, his right arm is held close to his body in a flexed and pronated position. Which of the following is the most likely diagnosis?? A: Proximal ulnar fracture, B: Anterior shoulder dislocation, C: Supracondylar fracture of the humerus, D: Olecranon fracture, E: Radial head subluxation,  <response>: This is a case of a 2-year-old boy with acute onset of right arm pain and inability to move the arm after the mother lifted him up by the arms. The description of the arm being held close to the body in a flexed and pronated position suggests a specific injury. The choices given include different fractures and dislocations around the elbow and shoulder. Based on the mechanism of injury being lifting by the arms and the presentation, the most likely diagnosis is a radial head subluxation, also known as nursemaids elbow. This occurs when the annular ligament surrounding the radial head slips off, causing the radial head to dislocate. It presents with sudden onset of pain and inability to move the affected arm. E: Radial head subluxation 