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': 'Smokeless gunpowder is composed of - \nSelect and explain. \nA. KMnO4, B. HCN, C. Nitrocellulose, D. Sulphur', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]