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': 'Onanism is: TN 07 \nSelect and explain. \nA. Natural sexual offence, B. Unnatural sexual offence, C. Perversion, D. Indecent assault', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. Perversion', 'role': 'assistant'}]