All open coronary sinus except?
Ans. B. Anterior cardiac veinThe coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the heart muscle. The coronary sinus drains into the right atrium, at the coronary sinus orifice, an opening between the inferior vena cava and the tricuspid valve. It returns blood from the heart muscle, and is protected by a semicircular fold, the valve of coronary sinus (Thebesian valve).
Middle cardiac vein
Anterior cardiac vein
Small cardiac vein
Great cardiac vein
Thorax