This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax: Aerial supply, Subject name: Anatomy
[{'content': "Aery supply to Koch's triangle is from: \nSelect and explain. \nA. Right coronary aery, B. Left coronary aery, C. Left anterior descending aery, D. Aery from anterior aoic sinus", 'role': 'user'}, {'content': "Answer: A \nExplanation: Koch's triangle (and AV node) is supplied by right coronary aery in majority of population. Koch's triangle boundaries tendon of Todaro opening of coronary sinus at the base septal cusp of tricuspid valve (. atrio ventricular valve) AV node at apex", 'role': 'assistant'}]