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
Which structure does NOT lie in the coronary sulcus? 
Select and explain. 
A. Circumflex aery, B. Coronary sinus, C. Right coronary aery, D. Right marginal aery
D: Right marginal aery
Answer: D: Right marginal aery 
Explanation: 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.