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: Forensic Medicine
[{'content': 'Calibre of a firearm is? \nSelect and explain. \nA. Distance between a land and groove, B. Distance between two diagonally opposite lands, C. Distance between two diagonally opposite grooves, D. None', 'role': 'user'}, {'content': "Answer: B \nExplanation: Distance between two diagonally opposite lands REF: Parikh 6th edition page 4.26 Caliber technicically means diameter of the inside of the bore (land to land) in 1/100' of an inch. Thus, caliber 22 means 22/100 inch= 0.22", 'role': 'assistant'}]