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: Pathology
[{'content': 'All of the following statements are true regarding down syndrome except? \nSelect and explain. \nA. Occurs due to meiotic non disjunction of chromosome 21, B. Trisomy 21, C. Most common CHD is enocardial cushion defect, D. It is the most common trisomy in humans', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Most common trisomy in humans is trisomy 16,most common type of autosomal trisomy that survive upto birth in trisomy 21.', 'role': 'assistant'}]