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: Anatomy
[{'content': 'If circumflex artery gives the posterior interventricular branch, this circulation is described \nSelect and explain. \nA. Right dominance, B. Left dominance, C. Codominance, D. Undetermined', 'role': 'user'}, {'content': 'Answer: B \nExplanation: In about 10% of hearts, the right coronary is rather small and is not able to give the posterior interventricular branch.\nIn these cases the circumflex artery, the continuation of left provides the posterior interventricular branch and called left dominant.', 'role': 'assistant'}]