This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetics, Subject name: Pathology
[{'content': "A married middle aged female gives history of repeated aboions for the past 5 years. The prenatal karyogram of the conceptus is given below: This karyogram suggests the following: \nSelect and explain. \nA. Klinefelter's syndrome, B. Turner's syndrome, C. Down's syndrome, D. Patau's syndrome", 'role': 'user'}, {'content': "Answer: C \nExplanation: Karyogram shows 3 chromosomes at 21 instead of a pair. It is called Trisomy 21. Trisomy 21 Synonymous with Down's syndrome Most common of the chromosomal disorders. Major cause of mental retardation. -Other trisomies Edward syndrome (Trisomy 18) Patau syndrome (Trisomy 13) Turners syndrome (45 X0)", 'role': 'assistant'}]