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: Gynaecology & Obstetrics
[{'content': 'Ovary develops from all except \nSelect and explain. \nA. Coelomic Epithelium, B. Yolk sac endoderm, C. Gonadal ridge mesenchyme, D. Urogenital sinus', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ovary develops from 3 major cellular sources\n\nPrimordial germ cells\nCoelomic epithelial cells\nMesenchymal cells from gonadal ridge.', 'role': 'assistant'}]