This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fetal circulation, Subject name: Pediatrics
[{'content': 'The hea assumes its normal four chambered shape by the end of:- \nSelect and explain. \nA. 4 weeks, B. 6 weeks, C. 8 weeks, D. 12 weeks', 'role': 'user'}, {'content': 'Answer: B \nExplanation: - The hea assumes its normal four chambered shape by the end of 6 weeks of intrauterine life. - From then, only minor changes occur & consist mainly on growth of the hea as a whole with increasing age of fetus.', 'role': 'assistant'}]