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': 'Which structure does NOT lie in the coronary sulcus? \nSelect and explain. \nA. Circumflex aery, B. Coronary sinus, C. Right coronary aery, D. Right marginal aery', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The coronary sulcus is the groove which separates the atria from the ventricles. The right and left coronary aeries, circumflex aery, and coronary sinus all lie in this groove. The right marginal aery is a branch of the right coronary aery which lies on the right ventricle and supplies that chamber of the hea.', 'role': 'assistant'}]