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
What is true about sinus venosus- 
Select and explain. 
A. Forms rough wall of right atrium, B. Forms smooth wall of right atrium, C. Forms right coronary sinus, D. Forms left leaflet of coronary sinus
B: Forms smooth wall of right atrium
Answer: B: Forms smooth wall of right atrium 
Explanation: None