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: Medicine
[{'content': 'Increased functional demand on the heart produces increased size of the myocardium by: \nSelect and explain. \nA. Hyperplasia, B. Hypertrophy, C. Calcification, D. Fatty infiltration', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]