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': "Which of the following skull fractures is called a Motorcyclist's fracture - \nSelect and explain. \nA. Ring fracture of base of skull, B. Hinge fracture of base of skull, C. Comminuted fracture of skull, D. Depressed fracture of skull", 'role': 'user'}, {'content': 'Answer: B \nExplanation: A transverse fracture across the floor of the skull, usually called a "hinge fracture", is sometimes referred to as motorcyclist fracture. At autopsy, the base of the skull may be appreciated to have divided into two halves, each moving independently of each other like a hinge, the so-called motorcyclist fracture.', 'role': 'assistant'}]