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': "The action of intramedullary 'K' nail is - \nSelect and explain. \nA. Two-point fixation, B. Three-point fixation, C. Compression, D. Weight concentration", 'role': 'user'}, {'content': 'Answer: B \nExplanation: K-nail is used for transverse or short oblique fracture of the femur, especially in the ischemic area.\nK-nail (Kuntscher cloverleaf intramedullary nail) provides three points fixation due to elastic deformation.\nThese three points of fixation are both ends of bone (2 points) and isthmus (3rd point).', 'role': 'assistant'}]