This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Gynaecology & Obstetrics
[{'content': 'Kidney size increases in pregnancy by \nSelect and explain. \nA. 0.5cm, B. 1.5cm, C. 2cm, D. 2.5cm', 'role': 'user'}, {'content': "Answer: B \nExplanation: Kidney size increases approximately 1.5 cm, returns to normal size in postpaum.(Ref: William's Obstetrics; 25th edition)", 'role': 'assistant'}]