This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Gynaecology & Obstetrics
[{'content': 'All the following are risk factors for fetal overgrowth except \nSelect and explain. \nA. Obesity, B. Diabetes, C. Primiparity, D. Previous macrosomic infant', 'role': 'user'}, {'content': "Answer: C \nExplanation: Risk Factors for Fetal OvergrowthObesityDiabetesPostterm gestationMultiparityLarge size of parentsAdvancing maternal agePrevious macrosomic infantRacial and ethnic factorsReference: William's Obstetrics; 25th edition; Chapter 44; Fetal-Growth Disorders", 'role': 'assistant'}]