This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pericardium & Heart, Subject name: Anatomy
[{'content': 'Great cardiac vein drains into - \nSelect and explain. \nA. Anterior cardiac vein, B. Coronary sinus, C. Thebesian vein, D. Venae cordis minimi', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Coronary sinus Veinous drainage of heart1. Coronary sinus: Opens into right atrium and has following tributries : (i) Great cardiac vein, (ii) Middle cardiac vein, (iii) Posterior vein of left ventricule, (iv) Small cardiac vein, (v) Oblique vein of left atrium and (vi) Sometimes right marginal vein.2. Anterior cardiac vein : Opens into right atrium.3. Venae cardis minimi (thebasian veins) : Open into right atrium.4. Right marginal vein : More often opens into right atrium but sometimes into coronary sinus.", 'role': 'assistant'}]