Which venous structure does not empty blood into the right atrium?

Entire Course Link

https://plus.google.com/u/0/108200033792883877670/posts/dWT4sDYbQKM

 
Which venous structure does not empty blood into the right atrium?

 




Coronary sinus
 


Inferior vena cava
 


Superior vena cava
 


Pulmonary vein