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
All opens into coronary sinus except - 
Select and explain. 
A. Middle cardiac vein, B. Small cardiac vein, C. Anterior cardiac vein, D. Great cardiac vein
C: Anterior cardiac vein
Answer: C: Anterior cardiac vein 
Explanation: Tributaries of the coronary sinus
-        Great cardiac vein
-        Middle cardiac vein
-        Small cardiac vein
-        Posterior vein of the left ventricle
-        Oblique vein of the left atrium
-        Right marginal vein sometimes.