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: Surgery
[{'content': 'What is the normal orientation of humeral head - \nSelect and explain. \nA. Retroversion of 80 degrees, B. Retroversion of 30 degrees, C. Anteversion of 15 degrees, D. Anteversion of 50 degrees', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Answer- B. Retroversion of 30 degreesNormal humeral retroversion is 25-35 degrees.Normal femoral anteversion is 8-15 degrees', 'role': 'assistant'}]