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': 'Which of the following bullets leaves a visible mark in path so that a person can see it: \nSelect and explain. \nA. Tandem Bullet, B. Tracer Bullet, C. Dum Dum Bullet, D. Incendiary bullet', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Tracer Bullet', 'role': 'assistant'}]