This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Injuries by Firearms, Subject name: Forensic Medicine
[{'content': 'All are components of black gun powder except: \nSelect and explain. \nA. Charcoal, B. Lead peroxide, C. Potassium nitrate, D. Sulphur', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans: b (Lead peroxide) Ref: Reddy, 27th ed,p. 187Components of black gun powder - Potassium nitrite 75%Sulphur 10%Charcoal 15%Smokeless gun powderNitrocelluloseNitroglycerineNitroguanidineSemismokeless powder80% Black gun powder + 20% smokeless powder- Lead peroxide is present in printing mixture.', 'role': 'assistant'}]