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
The coronary sinus - 
Select and explain. 
A. Lies in anterior part of the coronary sulcus, B. Ends in right atrium, C. Has venae cordis minimae as its tributaries, D. Develops from right anterior cardinal vein
B: Ends in right atrium
Answer: B: Ends in right atrium 
Explanation: Development of coronary sinus is from the body and left horn of sinus venosus. It lies in the posterior part of the coronary sulcus and drains into the right atrium. Though the besian veins/ venae cordis minimae drain directly into the right atrium, the the besian valves are guarding the opening of coronary sinus into the right atrium.