This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Social and Language Milestones, Subject name: Pediatrics
[{'content': "'Jargon' speech comes at:- \nSelect and explain. \nA. 6 months, B. 9 months, C. 15 months, D. 12 months", 'role': 'user'}, {'content': 'Answer: C \nExplanation: 15 months - Jargon speech', 'role': 'assistant'}]