This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
[{'content': 'Base of the hea is formed by \nSelect and explain. \nA. Right atrium, B. Right ventricle, C. Left atrium, D. Left ventricle', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Base of hea is formed by left atrium and the small pa of right atrium. BD CHAURASIA&;S HUMAN ANATOMY.VOLUME 1. 6TH EDITION.PAGE NO 253', 'role': 'assistant'}]