This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Orthopaedics
[{'content': 'A 18 years old boy with history of Anterior dislocation of shoulder presents with \nSelect and explain. \nA. Abduction and internal rotation, B. Abduction and external rotation, C. Flexion, D. Extension', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]