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': 'Lowest frequency of twin pregnancy is seen in: \nSelect and explain. \nA. Nigeria, B. Philippines, C. India, D. Japan', 'role': 'user'}, {'content': 'Answer: D \nExplanation: <p> Lowest frequency of twin pregnancy is seen in Japan(2/1000). Reference:Textbook of obstetrics,Sheila Balakrishnan,2nd edition,page no:178. <\\p>', 'role': 'assistant'}]