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': 'Impoant factor for discordant growth between twins is: \nSelect and explain. \nA. Anaemia, B. Twin to twin transfusion, C. Compression, D. All', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Twin to twin transfusion', 'role': 'assistant'}]